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Christian Character and Conduct

Bible Question: My boss says that the Bible says to take care of yourself, and quotes "Do you not know that your body is the Temple of the Holy Spirit. .?" I feel more is said about serving OTHERS and God takes care of US. Which is it?

Answer: The scripture reads: " Know ye not that your body is the temple of the Holy Spirit which is in you, which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's." 1 Corinthians 3:16 says "Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in You?" Ephesians 2:20-22 says that we "are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone; in whom all the building fitly framed together groweth unto an holy temple in the Lord: in whom ye also are builded together for an habitation of God through the Spirit."
The Apostle Paul refers to Jesus' followers as the temple of God, sometimes in a collective sense and sometimes individually. This is only true if one is in Christ — begotten of the Holy Spirit. Otherwise this body is not a temple at all, and serves no purpose for God. Yes, we should take care of our bodies (health wise), but only for the purpose of serving God and others. Primarily we should take care of our spiritual interests, growing in grace and truth.
This is a tremendous privilege—to be God's children and to have His holy spirit and influence in us. In Jewish times, the temple, and before that, the tabernacle, were places where the people would go to serve God and receive His blessings and learn of His ways. We are the temple of God now as we strive to glorify God and show His wonderful plan to others. But we will have an even more wonderful opportunity to do this on a grander scale once we have been resurrected in Heaven and once God's Kingdom on earth begins.
There have been millions throughout the ages who have not learned of Christ, and yet Paul states that Christ "gave himself a ransom for all, to be testified in due time." (1 Timothy 2:4-6) All Christians realize that for the past 2000 years God has been "calling out a people for his name." (Acts 15:14) Those who believe now, during this difficult, evil time will be rewarded for their faith by receiving life in heaven. "If we suffer, we shall also reign with him . . ." (2 Timothy 2:12)
But, what will happen to the millions throughout the ages who never learned of Christ? Not all people have ears to hear today, and not all have their "due time" at the same time. Jesus gave his life so that all would receive a resurrection and a reasonable opportunity to know him and gain everlasting life. "As in Adam all die, even so in Christ shall all be made alive." (1Corinthians 15:22)
This is the glorious purpose for the reign of Christ with his Church! Those who prove faithful as Christians now will have the privilege of bringing all up from the grave to learn of Christ in that wonderful time. Christ and his church will teach righteousness to these billions during this kingdom when learning will be more favorable for them.
God has given us the promise that, if we are faithful now as Christians in following Christ and doing His will, we will be resurrected in heaven. Jesus promises us in Revelation 5:9 and 10 that we will be made priests and kings, and that eventually we will reign over the earth to bless and teach the people. During the Millennium, when God's kingdom for which we pray is established here on earth by Christ, all the rest of mankind will be resurrected here on earth and learn of God's loving plan. That will be in the kingdom for which we pray "Thy kingdom come, Thy will be done on earth as it is done in heaven." That will be when "The earth shall be full of the knowledge of the Lord as the waters cover the sea." (Isaiah 11:9) The Scriptures assure us that every person who has ever lived will be brought back to life on earth at that time. "The hour is coming, in the which all that are in the graves shall hear His voice, and shall come forth; they that have done good [in this evil age], unto the resurrection of life: and they that have done evil [those not justified by faith now], unto the resurrection of judgment." (John 5:28, 29 RSV) "When thy judgments are in the earth, the inhabitants of the world will learn righteousness." (Isaiah 26:9) They will then be given the opportunity to learn from their past mistakes. "They also that erred in spirit shall come to understanding, and they that murmured shall learn doctrine." (Isaiah 29:24) They will learn of Christ' s loving sacrifice for their sins. They will then have the opportunity to repent of their sins and accept Christ and obey Him. Those who do so will be gradually brought up to human perfection as Adam had before he sinned. If they are faithful then, they will eventually be granted everlasting life here on earth. We will have the blessing of teaching them. In that way we can be the "temple" of God then, too. We can bless the people and help bring them to Christ. Revelation 21:2-4 says that we will be a "holy city," a "bride adorned for her husband," a "tabernacle of God," and what wonderful things will happen! "And I John saw the holy city, new Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband. And I heard a great voice out of heaven saying, Behold, the tabernacle of God is with men, and He will dwell with them, and they shall be His people, and God himself shall be with them, and be their God. And God shall wipe away all tears from their eyes, and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away."
All mankind, during the Millennium, will be privileged to draw near to God and to receive divine favors and uplift out of sin and death, back to the original image and likeness of God, which Adam lost in Eden, and which Christ redeemed for all at Calvary. And we will be permitted to help them in that kingdom if we are faithful now in serving God!
Serving Others
There is quite a bit said in the Bible about serving others and sacrificing for the Lord and for others. We are told in Romans 12:1, "I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service." Colossians 3:1-3 says, "If ye then be risen with Christ, seek those things which are above, where Christ sitteth on the right hand of God. Set your affection on things above, not on things on the earth. For ye are dead, and your life is hid with Christ in God." Colossians 1:24 says, "Who now rejoice in my sufferings for you, and fill up that which is behind of the afflictions of Christ in my flesh for his body's sake, which is the church." Galatians 6:9 and 10 says, "And let us not be weary in well doing: for in due season we shall reap, if we faint not. As we have therefore opportunity, let us do good unto all men, especially unto them who are of the household of faith." In Philippians 2:30 we are told of the good example of Epaphroditus who, "Because for the work of Christ he was nigh unto death, not regarding his life." Sacrificing ourselves (including our time, our health, our desires) to serve the Lord and to help others is a Scriptural principle for those who belong to the Lord. Sickness and discomfort of any sort, incurred by our energy in the service of the Lord and His truth, are permitted by our Father as evidences of our fidelity and love; because if not liable to such tribulations, or if relieved of them instantly by a miracle, the Lord's service would cost us no sacrifice and the test of our willingness to endure for the Lord or the truth's sake would be wanting. As it is, however, every ache or pain or wound of person or of feelings for the Lord's sake, becomes a witness of the spirit, testifying to our faithfulness. And in all such tribulations we should rejoice greatly. "If any man suffer as a Christian, let him not be ashamed; but let him glorify God on this behalf." (1 Peter 4:16)
Of course, this doesn't mean we should plop down on the couch all day and eat cream donuts. We don't want to serve our own fleshly inclinations. We want to serve God and others. The rest of 1 Corinthians 19 and 20 says, "Ye are not your own . . . For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's." We want to be able to serve the Lord and His cause to the best of our ability, and this requires a reasonable care of our bodies. Everything we do, we want to do to the glory of God. Our main goal is not a strong physical body, but to sacrifice that physical body to serve God. We will then develop a strong spirit. 1 Timothy 4:7 and 8 says, "Exercise thyself rather unto godliness. For bodily exercise profiteth little, but godliness is profitable unto all things, having promise of the life that now is, and of that which is to come." It doesn't say that bodily exercise doesn't profit at all, but that it profits "little." It only helps if it enables us to serve God better. Our time belongs to the Lord, and we want to use that time in ways that will be pleasing to Him.

Bible Question: How can I know what God wants me to do? How do I know if this is the right thing to do or if I'm doing it in the right way?

Answer: It is sometimes difficult to discern God's will for us in our life. But God is developing us through faith, so we should not expect Him to directly tell us what we should do. In order to better understand what God's will is, it is essential to study God's Word and listen (figuratively) to the leading of God's Holy Spirit. Of course, those who have not made a commitment to God (consecration to do his will, Rom. 12:1) will not be lead of the Holy Spirit. It is only for those in this covenant relationship (through baptism) with God. We recommend the following book that is very helpful to study the Bible and God's plan: htdbv5/indexa.htm
Prayer, of course, is a big factor in knowing what God wants us to do. James 4:8 tells us, "Draw nigh to God, and he will draw nigh to you. Cleanse your hands, ye sinners; and purify your hearts, ye double minded." As we draw closer to God, He will further reveal his will for us through His Word and through the experiences He allows us to have.
As James 4:8 says, in order to draw night to God, we also need to avoid sin in our life. Those who want to go further after cleaning up their life are encouraged to consecrate their life to God by giving up their own will and seeking to do God's will in their life, through the merit of Christ's ransom sacrifice. They are to daily lay down their lives in sacrifice, as Romans 12:1 states, "I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service."
There is a special privilege of prayer given to all who have made a full consecration of their lives to God, dedicating themselves to follow in Christ's footsteps. Those who have become a "new creature" (2 Cor. 5:17) have an advocate — Christ Jesus. As their advocate, Christ covers their imperfection with the robe of his own righteousness and presents them justified [made right] to the Father. Then these "new creatures" are given the special privilege of prayer, that they may "come boldly unto the throne of grace" (Hebrews 4:16) at any time, day or night. It is through prayer, study, and providential overrulings that God reveals His will to His consecrated children.

Bible Question: 1John 3:6 - I believe I am saved by the blood of Jesus, but I still sin. (Romans 7) So how does the blood still cover me?

Answer: God is opposed to sin, and as much as we are following Him, in proportion we are to also hate iniquity but to love righteousness. But we are still of the human nature, we still "live in the flesh" as much as we want to and try to "live by the spirit." What the Apostle is referring to in this scripture is sin in it's fullest state, that is willful transgression of the divine law. Not all sins are this willful nature, as there are sins in which wilfulness is not complete, since they are the results of temptation, and sins that are the results of our own weaknesses through the Adamic fall. Such weaknesses and such stumblings under temptation belong to the flesh which is already reckoned dead (in the true Christian) and is not reckoned of God as belonging to the Christian. As you mentioned Romans 7 also explains this. Our God judges us not according to the flesh, but according to the spirit.
However, there are some partial sins—weaknesses of the flesh, and of where these weaknesses of the flesh that the mind failed to be as strong and courageous as it should have been, and to some extent yielded to the wrong-doing. With these God does deal with these with chastisements, in order to help them learn their lesson and be stronger in the future. We should be especially on our guard to not allow sin to deceive us and to partake in what we know God disapproves of.

Bible Question: Bad habits. How do you overcome something that you keep going over and over again?

Answer: The great work of the Christian during this present time is the process of putting off the old defilements (bad habits) and putting on the new character. The Apostle Paul speaks of this work in Colossians 3:9,10
Having put off the old man with his practices...put on the new one...........
What is it to put off the old nature, and how do we put on the new? According to the Apostle instructs we must set our affections on the things above, the heavenly things & at the same time we are to put to death our fallen fleshly desires. (Col. 3:1-5)
1 If ye then be risen with Christ, seek those things which are above, where Christ sitteth on the right hand of God. 2 Set your affection on things above, not on things on the earth. 3 For ye are dead, and your life is hid with Christ in God. 4 When Christ, [who is] our life, shall appear, then shall ye also appear with him in glory. 5 Mortify therefore your members which are upon the earth; fornication, uncleanness, inordinate affection, evil concupiscence, and covetousness, which is idolatry:
As Christians (New Creatures in Christ Jesus) we are declared to be dead to the world, and alive toward God through Jesus Christ our Lord. But this metaphor applies wholly to our transformed hopes and aims and ambitions, while this " new mind" must still operate through the old human body until the resurrection change. In reality, we have an enemy very close to us all the time—our old self. That "old man" would like to have you off guard to keep you from carefully scrutinize your thoughts, words & acts. You must not mind what the old man says; instead, listen for the Lord's voice, listen to his clear instructions through the Apostle, kill (" Mortify" ) the old man.
A large part of your difficulty, and the difficulties of all who seek to walk in the narrow way, is that the old man cries out and wants to retain liberty and life, but this is contrary to the interests of the New Creature, so no attention should be paid to it. Every time a contrary thought comes to mind, the old man must be told that he was put to death long ago & he will not have his way! Then we must replace these thoughts with the higher thoughts, the spiritual. The Apostle Paul tells us in (Rom. 12:2) that if we do this we will be transformed & The Apostle John says in (John 8:31,32) that we will be set free (free from doctrinal errors, free from immoralities, etc.)
(Rom. 12:2) And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what [is] that good, and acceptable, and perfect, will of God.
(John 8:31, 32) If ye continue in my word, then are ye my disciples indeed. And ye shall know the truth and the truth shall make you free.
While instructing us to be dead toward earthly things and alive only toward the heavenly things, the Apostle doesn't counsel us to retire from the world, instead he tells us how to deaden our appetites, desires, etc., that are rooted and grounded in our fallen flesh. He mentions these fallen tendencies, starting with the grosser and ending with the most subtle, in Colossians 3:1-5.
The Apostle Paul speaks of struggles with the bad habits of his flesh in Romans 7: 15-25 —
"For that which I do I allow not: for what I would, that do I not; but what I hate, that do I. If then I do that which I would not, I consent unto the law that [it is] good. Now then it is no more I that do it, but sin that dwelleth in me. For I know that in me (that is, in my flesh,) dwelleth no good thing: for to will is present with me; but [how] to perform that which is good I find not. For the good that I would I do not: but the evil which I would not, that I do. Now if I do that I would not, it is no more I that do it, but sin that dwelleth in me. I find then a law, that, when I would do good, evil is present with me. For I delight in the law of God after the inward man: But I see another law in my members, warring against the law of my mind, and bringing me into captivity to the law of sin which is in my members. O wretched man that I am! who shall deliver me from the body of this death? I thank God through Jesus Christ our Lord. So then with the mind I myself serve the law of God; but with the flesh the law of sin."
The Apostle represented not only himself but all sincere followers, groaning under the Law, when he cried out, "O wretched man that I am! Who shall deliver me from this dead body?" (Rom. 7:24.) He was mourning, and the Lord appointed that all the mourners in Zion should be comforted-(Mat. 5:4)-comforted with the assurance that, while they were sinners and imperfect and could never justify themselves before God under the Law, nevertheless, God himself had found a ransom, had redeemed his people (1Tim 2:4-6). It is in view of this comforting assurance of the Gospel that the Apostle, after representing himself as the Jew, under the Law, groaning and travailing, and crying for deliverance, in the next breath represents himself as the Christian who has found the deliverance, and exclaims, "Thanks be unto God, who giveth us the victory through our Lord Jesus Christ!"
We can't keep the Law in our flesh because our flesh has inherited various weaknesses and fallen tendencies. But we are to continually strive against these inherited weaknesses. But by the Lord's grace we have forgiveness of our sins through our Lord Jesus. And as true Christians our hearts desire is to do the will of God, his will becomes our will, our mind. So with this new mind (or will) we can do perfectly, that is we can be perfect in our heart intentions.

Bible Question: What does the bible say about suing someone? And where, what scriptures?

Answer: The guidelines are different if the aught is against another fellow Christian, compared to being against someone in the world. We have listed scriptures about both situations below. Jesus spoke to the issue of Christians being sued by the worldly in Matthew. (Mat 5:40) And if any man will sue thee at the law, and take away thy coat, let him have thy cloak also. This refers to a Christians responsibility in his dealings with the world.Christians are to be law-abiding, whether they consider the laws just or unjust.
The Apostle Paul speaks of Christians suing fellow Christians. He warns against suing a brother in a court of law. Instead he suggests that we settle it by judgement of the church or else we endure the injustice. I Corinthians 6:1-7 addresses this issue.
(1Cor. 6:1) Dare any of you, having a matter against another, go to law before the unjust, and not before the saints? The unjust refers to earthly courts, those who have not been justified by the blood of Christ.
(1Co 6:2) Do ye not know that the saints shall judge the world? and if the world shall be judged by you, are ye unworthy to judge the smallest matters? The judging will be in the nature of a trial or testing, to determine how many of humanity can be helped up to perfection.
(1Co 6:3) Know ye not that we shall judge angels? how much more things that pertain to this life?
Refers to a trial or testing of these spirits in prison who were once disobedient, in the days of Noah; this implies a hope for them. The holy angels need no trial, no judging.
(1Co 6:4) If then ye have judgments of things pertaining to this life, set them to judge who are least esteemed in the church.
If they have lost confidence in the leaders whom the Lord has set in the Church, they should at least choose as judges the least esteemed in the Church as preferable to a court of unbelievers.
(1Co 6:5) I speak to your shame. Is it so, that there is not a wise man among you? no, not one that shall be able to judge between his brethren?
(1Co 6:6) But brother goeth to law with brother, and that before the unbelievers.
If they had no confidence in each other, they at least should not manifest more confidence in outsiders.
(1Co 6:7) Now therefore there is utterly a fault among you, because ye go to law one with another.
Why do ye not rather take wrong? why do ye not rather suffer yourselves to be defrauded?
We should rather suffer wrong and take injury from a brother in Christ than take the matter before the world of unbelievers and thus risk a general odium upon the Lord's cause.
We are not given specific do's and don'ts in Gods word concerning this issue. The Christian is at liberty not under the Law, therefore he is to consider what would best honor and glorify his cause as a son of God. There may be times when for the protection of others and for the defense of truth it would be necessary to appeal to the Law. The Apostle Paul appealed to the Law, to maintain his influence for the Christian cause. To read further see: htdbv5/htdb0147.htm

Bible Question: How can I overcome bitterness?

Answer: It is very difficult to overcome bitterness until you understand why their is evil in the world today, and to be able to separate the sin from the person. People today are not much different than a dog that always snaps and bites when afraid. That dog was conditioned to be that way by either being abused by its owners, or by being a stray and very afraid, by being born in the wild and never knowing the love of a human, or heredity of a bad trait from its parents. But, do we hold all this against that dog? Do we have bitterness toward that dog? No, we just feel sorry for it.
Humans can be affected by their heredity or environment in the same way, and turn out to be mean and sinful. Many people are simply mentally ill and can't help themselves. We are not to feel good about the sinful thing someone does, but if we separate the sin from the sinner, separate that behavior from the person that maybe does not really desire to be that way, then we will have sympathy for that person — just as for that dog.
In God's kingdom, all will have to learn of God's ways and will have a chance to be good. The deceiving influence of Satan will be removed, and the inherited sinfulness will also be removed. Then, these same people that were so bad, might turn around and be good.
This is what it means to "love thine enemy" — not to love the evil that your enemy did, but to try to see what the person might be like if all the factors out of their control that made them mean and evil were removed.
After understanding the above reasons why people can be evil and disappoint us, a practical way to overcome bitterness is to pray for those who anger us. It is very difficult to still stay bitter if we sincerely pray for them.

Bible Question: how to deal with the pressures of life?

Answer: " For thus saith the Lord GOD, the Holy One of Israel; In returning and rest shall ye be saved; in quietness and in confidence shall be your strength." Isaiah 30:15
What it means is that our spiritual strength and freedom from the pressures of life comes from understanding God's plan of salvation and doing those things that show that we are in harmony with Him and His plan. When we do those things, we enter into a rest that revives us. 1 Pet 5:7 "Casting all your care upon him; for he careth for you."
Peace — the opposite of worry:
Jesus said: " Come unto me, all ye that labor and are heavy laden, and I will give you rest." (Matt. 11:28) Each Christian, in proportion to his or her knowledge and faith, will have rest and peace within themselves. " We which believe do enter into rest." The perfect time of rest for Christians comes when we submit our all to the Lord, accepting joyfully his promised guidance through a " narrow way" to the Kingdom. There we rest from our own works, from all effort to justify ourselves. There, we confess ourselves to be imperfect and unworthy of Divine grace, and unable to make ourselves worthy. There we gratefully accept Divine mercy extended toward us in the redemption which is in Christ Jesus our Lord.
But this rest we have entered into is not our ultimate rest. A permanent rest awaits us: " There remaineth therefore a rest to the people of God.... Let us labor therefore to enter into that rest, lest any man fall after the same example of unbelief." (Heb. 4:9-11) Christians will enter into that rest when they experience their resurrection change, when they will enter into the joys of their Lord.
The word Sabbath signifies rest or peace, and, therefore, its deeper significance was to lead the Jew to Christ and have the burden of the Law lifted. No Jew was able to gain life under the Law Covenant, but by becoming dead to the Law, he was privileged to come into membership in Christ— become a sharer in the covenant of sacrifice. (Rom. 7:4-6 and Psa. 50:5) So doing, he was promised rest from the Law and its condemnation, because " There is therefore now no condemnation to them that are in Christ Jesus." (Rom. 8:1) Indeed, the merit of Christ covers the shortcomings of all those who are striving to walk in his steps, and the Scriptures give them the assurance of Divine favor, ushering them into peace with God through our Lord Jesus Christ.
John 14:27 Peace I leave with you, my peace I give unto you: not as the world giveth, give I unto you. Let not your heart be troubled, neither let it be afraid.

Bible Question: Where does the Bible about not marking your skin? So many people draw on their hands & leave messages & I know it says not to do that sort of thing, unless it was referring to tattoos.

Answer: Here is the verse you are looking for in two translations:
Leviticus 19:28 King James Version: "Ye shall not make any cuttings in your flesh for the dead, nor print any marks upon you: I am the LORD."
Leviticus 19:28 New American Standard Version: "You shall not make any cuts in your body for the dead, nor make any tattoo marks on yourselves: I am the Lord."
Actually, "for the dead" is not a good translation —- it would be properly rendered "for the soul." See the margin of most Bible translations.
Any marks on the skin, whether messages or tattoos would be contrary to the Law given to the Jews. Even though the Law is not binding upon Christians, because Jesus fulfilled the Law and freed his followers from its bondage, there is still good reason why God set these Laws into place. It was for the protection of His people that they might keep healthy. Also, marking the skin was a practice of paganism, such as found in ancient Egypt and Babylon, therefore, it was also to keep His people from identifying with these pagan practices.

Bible Question: Wearing gold, jewelry, ornaments, earrings against Christianity?

Answer: According to the New Testament, "adornments" are to be minimized as they may be a source of pride or arrogance. Some Christian groups ban all jewelry, but we would not make it a rule, but advise moderation in all things.
(about women)
1Pe 3:2 as they observe your chaste and respectful behavior.
1Pe 3:3 Your adornment must not be merely external—braiding the hair, and wearing gold jewelry, or putting on dresses;
1Pe 3:4 but let it be the hidden person of the heart, with the imperishable quality of a gentle and quiet spirit, which is precious in the sight of God.
Rom 12:2 "And be not fashioned according to this world: but be ye transformed by the renewing of your mind, and ye may prove what is the good and acceptable and perfect will of God."

Bible Question: Is there anything in the bible about smoking?

Answer: God sets down principles of conduct and then leaves it to each individual to decide what is proper and what is improper. The Scriptures state that we are "ambassadors for Christ." Whatever we do, we "should do all to the glory of God." If our behavior can be misunderstood by others, we should really consider whether this is glorifying God. 2Pet. 3:11 states: "Seeing then that all these things shall be dissolved, what manner of persons ought ye to be in all holy conversation and godliness..."
The Apostle Paul said that "all things are lawful for me, but not all things are expedient." In other words, even if there are things that are now lawful, because a Christian is not under the law, there are things that might not be good to do because it would stumble or harm others or harm ourselves.
The Christian is admonished to live a "sanctified" life apart from the world. If Jesus where to walk in and come up to you, would he join in with what you are doing, or would he say, "My child, what are you doing here?" Only you can answer this question.
As for the person who is smoking, you will not find anything specific in the Bible that will tell you that it is not honoring God. Again, there are only principles of righteous living. For example, you will not find anything in the Bible that says that you should not eat rocks, but it is common sense not to do so. There is nothing in the Bible that says you should not inhale glue, but it is common sense not to do so. There is nothing in the Bible that says that you should not jump out of a 10 story window, but it is common sense not to do so. In the same way, you will not find anything that says you should not smoke, but it is common sense not to do so. The Bible calls the body the temple of God — why would we chose to defile it? (1Corinthians 6:19)

Bible Question: Swearing - explain what Matthew 5:34 means?

Answer: " Ye have heard that it hath been said by them of old time, Thou shalt not forswear thyself, but shalt perform unto the Lord thine oaths: But I say unto you, Swear not at all; neither by heaven; for it is God's throne: Nor by the earth; for it is his footstool: neither by Jerusalem; for it is the city of the great King. Neither shalt thou swear by thy head, because thou canst not make one hair white or black. But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil." Matthew 5:33-37
While profanity is addressed in God's law, this commandment is about making oaths. An example of the ancient law that Jesus referred to is, " If a man vow a vow unto the LORD, or swear an oath to bind his soul with a bond; he shall not break his word, he shall do according to all that proceedeth out of his mouth." Numbers 30:2
Jesus said that of old time it had been said " not to forswear thyself" . Forswearing yourself would be like perjury in our system of justice today. This is a violation of the law in Numbers 30:2
Because the people who run our court systems are accustomed to hearing witnesses lie on the stand, we have a custom of " swearing in" a witness before they give their testimony. This custom says to the witness, " we expect the truth from you, the truth, the whole truth, and nothing but the truth. And, if you should decide to bear a false witness to us, there is a consequence for you of the charge of perjury." This oath taking is both proper and necessary.
But, in a similar way, people are so accustom to lies and lying that it was common, even in Jesus' day, to qualify a statement with an oath saying basically, " OK, I may sometimes lie, but I swear that this thing I am saying is true." He may use some object of value to qualify his oath. " I swear on my mother's grave"...This is what Jesus' command prohibits.
While on the surface it may seem harmless enough, the use of oaths implies that the simple statement of the user is not to be believed. The fact that one swears what he says is true implies that he does not expect his hearer to believe his simple word, and this in turn presupposes that his word ordinarily is not worthy of belief.
Tell the truth! Be so truthful in all that you say that it will be unnecessary to swear to its truthfulness. Neither overstate nor understate the truth.