The Sermon on the Mount: Oaths

You Have Heard It Said

The quotation that Jesus gives, “You shall not swear falsely, but shall perform your oaths to the Lord” is not found in the Old Testament. There are statements that come close. For instance, in Leviticus 19:12 God commands, “you shall not swear by My name falsely” and in Numbers 30:2 we read, “If a man makes a vow to the LORD, or swears an oath to bind himself by some agreement, he shall not break his word; he shall do according to all that proceeds out of his mouth.”

Perhaps one could claim that the statement Jesus quotes is merely a summary of the Old Testament teaching, but if you consider the statement carefully, there is a subtle flaw. The statement affirms that oaths made to God must be kept, but what about other promises? Does a person have to keep his word if he did not swear to God to do something?

According to the Mishna, a Jewish commentary on the Law, “Oaths may only be taken about what can be defined according to size, weight, or number.” In other words, a promise is not considered binding unless it was bound by something tangible that could be, at least in theory, redeemed if a person broke his oath. “If a claim concerns these, no oath is imposed: bondsmen, written documents, immovable property, and the property of the Temple.” In other words, the claimant against a broken oath must have at least a remote chance of collecting on the broken promise if the promise is to be considered valid. Further, the Mishna states that oaths made with the phrase “I adjure you,” “I command you,” or “I bind you” were binding, but a vow made with phrases such as “by heaven and earth” were not binding. Thus, it mattered to a Jew how an oath was worded as to whether it was binding or not.

But I Say to You

Whether a person is giving an oath, swearing a truth, giving a promise, or taking a vow all refer to making a commitment that is bound by something else. Through the ages, people have used various things to bind their words, such as their possessions, their reputation, their religion, or their life. Anything that another person would accept can be offered to bind a person’s commitment.

We use oaths frequently in modern life and often don’t think about it. When purchasing a car with money loaned to us from the bank, we sign a statement with the bank promising to pay back the loan, and offering as collateral, the car we are purchasing. The bank doesn’t just take our word that we will pay what we owe. Our word is bound by a physical possession that the bank can take possession of if we do not keep our promise. Legal documents, such as our tax forms, contain statements above the signature line stating that we promise that what we have submitted is true to the best of our knowledge and giving the government the right to incur penalties against us if we have given false or misleading information.

Oaths and swearing in this discussion do not refer to cursing or foul language, though these words do carry a double meaning in the English language. There are numerous verses that can be used to demonstrate that cursing is wrong, but the verses we are studying are not the proper ones to use.

In Matthew 5:34-36, Jesus gives a list of things not to swear by: heaven, God’s throne, the earth, Jerusalem, or the hair on your head. Each example would be an oath that Jews would have considered being non-binding. Thus, Jesus is forbidding the making of non-binding oaths, or hypocritical oaths if you would.

When Jesus said, “swear not at all,” he was not forbidding all oaths. The Bible contains several examples of proper oaths. God swore an oath to Abraham based on Himself (Hebrews 6:13-17). God didn’t do this because His word wasn’t trustworthy, but He placed His reputation on the line to prove to the world His faithfulness. Jesus was under oath when he was on trial (Matthew 26:62-64). Paul took a vow while in Antioch (Acts 18:18). These oaths were acceptable because those taking them meant to keep their promises. Making an oath with no intention of carrying it out would be lying.

Instead, Jesus states that oaths are not needed by Christians. The reason people feel the need for an oath is because of Satan’s activity in the world. Satan is the father of lies and liars (John 8:44). It is because worldly people lie that those in the world insist on having something more than a simple “yes” or “no.”

Old Testament Teachings on Oaths

The entire chapter of Numbers 30 deals with the subject of vows. In general, oaths are binding, but provisions are made for oaths made by a dependant. When a person is dependant on another for his livelihood, such as a child or a wife, the dependant’s vow is not binding on the head of the household unless he directly affirms the promise or does not contradict it within a day of learning about the promise. Notice especially Numbers 30:2; the vows under consideration are not just those given to the Lord. All oaths are covered by these laws.

Even when the oath was detrimental to the swearer, it was to be kept (Psalm 15:4).

Oaths to God are not a separate category but emphasized as especially important to keep (Ecclesiastes 5:4-6). Everyone should take God very seriously because He holds our life in His hands. But when a vow is made in God’s name, the performance of the one making the vow becomes a reflection on God and His reputation. When a person breaks his word sworn in God’s name, he places both himself and God in a bad light in the eyes of those accepting the oath. Unfortunately, people often take an “out of sight, out of mind” attitude toward God. Because they don’t have immediate reminders or retribution, they allow things to slip.

Oaths were not required under the Mosaical Law to bind agreements. Israelites were expected as a matter of course to deal honestly with their fellow men. “You shall not steal, nor deal falsely, nor lie to one another” (Leviticus 19:11). God has been consistent with His attitude towards falsehoods (Proverbs 12:22). “These are the things you shall do: speak each man the truth to his neighbor; give judgment in your gates for truth, justice, and peace; let none of you think evil in your heart against your neighbor; and do not love a false oath. For all these are things that I hate,' says the LORD” (Zechariah 8:16-17). This last passage is much like Jesus’ teaching on oaths. You are better off giving no oath than to give a false oath.

New Testament Teachings on Oaths

James echoes Jesus teaching in James 5:12. Oaths are unnecessary for the Christian because Christians are commanded not to lie (Colossians 3:9; Ephesians 4:25). If everyone always told the truth, then there would be no need for oaths.

The world might require oaths from a Christian because they are used to dealing with liars. But the existence of an oath will not change a Christian’s behavior. He will carry out his word regardless of whether a vow accompanied it or not.

What about swearing by God’s name? The New Testament contains several examples. “For God is my witness ...” (Romans 1:9; Philippians 1:8). “I call God as a witness against my soul ...” (II Corinthians 1:23). “... before God, I do not lie ...” (Galatians 1:20). We can conclude that one can swear by God’s name, but we must be aware that as God warned the Israelites, our performance will reflect on God. Therefore, a Christian should do so rarely and with care since we know so many things are beyond our control (James 4:13-16).