“Again, 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).

We come now to the fourth antithesis or contrast that Christ brings to our attention. We have seen that the first contrast has to do with the Sixth Commandment while the second and third have to do with the Seventh Commandment. This fourth antithesis has to do mainly with the Ninth Commandment, which says, “Thou shalt not bear false witness against thy neighbour.” 

In verse 33, the Lord states what the Jewish Rabbis said concerning the matter of oath taking, “Thou shalt not forswear thyself, but shalt perform unto the Lord thine oaths.” Now this is not a direct quotation from the Old Testament but it is a summary of various passages concerning oaths such as Leviticus 19:12, Numbers 30:2 and Deuteronomy 23:21. There is nothing wrong in the words of the Rabbis at this point, but what is wrong comes out clearly in the next few verses where Christ rebukes them and exposes their fault.

The scribes and Rabbis had taught that an oath that is sworn to the Lord or in the name of God must be kept. However, an oath that is not made in direct connection with God’s name but with other objects such as heaven or Jerusalem is of a lesser significance and a person did not need to be so careful and conscientious about keeping it. The scribes thought that by using a substitute for God’s name when taking an oath, they could still keep the emphasis on the truthfulness of a person’s statement but without absolutely binding or obligating him to the truth.

Thus for example, if you wanted someone to believe what you are saying but you did not want to commit yourself fully to it, you could say “I swear by Jerusalem that what I’ve said is true.” But later on, if it turns out that your statement was false or that you did not keep to your word, then it was not so bad because God’s name had not been used in the first place, and you are not subjected to the same kind of punishment as when God’s name had been used.

And so what happened in those days was that oaths began to multiply in daily conversations. It became a very common thing to swear in order to make an impression or to spice up the conversation. Heaven, earth, Jerusalem, the temple, the altar and other objects were being invoked in oaths as substitutes for God’s name.  

Christ exposed the utter hypocrisy and foolishness of such an approach to oath taking. He says in verses 34-36 that we are not to swear by heaven, for it is God’s throne. We are not to swear by earth for it is God’s footstool. We are not to swear by Jerusalem for it is the city of the great King and we are not to swear by our own head for we cannot even change the intrinsic or natural colour of our hair.

What Christ is teaching is this – that it does not matter what object you choose to invoke or swear by, in the final analysis you are swearing by God for He is the creator and owner of this entire universe; and such oaths are just as binding as those where the name of the Lord had been expressly used. Furthermore, no where in scriptures are we taught to swear by anything other than God.

But at this point, someone might ask, “How do we reconcile the fact that the Bible, in quite a few places, especially in the Old Testament, allows for the use of oaths whereas Christ says, “Swear not at all?” Is the Lord setting aside the Old Testament law regarding oaths? And is He telling us that all oaths without exception are absolutely forbidden?” There are some groups like the Jehovah’s Witnesses and the Anabaptists who have understood these verses absolutely literally and have thus refused to take oaths even in court. But this is not the right interpretation of the text.

Firstly, we must remember the context – that Christ was correcting the errors of the Rabbis and scribes. He was not in any way setting aside or abolishing the Old Testament law. He came not to destroy but to confirm it. Secondly, we have many examples in Scripture of oath taking. God Himself takes an oath. Hebrews 6:13, “For when God made promise to Abraham, because he could swear by no greater, he sware by himself…” and again in Hebrews 6:17 “Wherein God, willing more abundantly to shew unto the heirs of promise the immutability of his counsel, confirmed it by an oath.” The Apostle Paul took various oaths in his epistles (Rom. 1:9, Phil. 1:8, 2 Cor. 1:23). And even Christ Himself testified before the Sanhedrin under oath (Matt. 26:63-64).

William Hendriksen says, “In this world of dishonesty and deception, the oath is at times necessary to add solemnity and the guarantee of reliability to an important affirmation or promise. Nothing either here in Matthew 5:33-37 or anywhere else in Scripture forbids this.”[1] In other words, because we live in a fallen world, God has provided for proper oath-taking and swearing in His name as a partial remedy for sinful men’s tendency towards dishonesty and a distrust of one another. The Lord knows that fallen men’s inclination to falsehood causes them to distrust each other, and so in certain situations of great importance and seriousness, an oath is taken in order to give greater motivation to the one making it to tell the truth or to keep to his word.

But what the Lord is absolutely forbidding in our text is all unnecessary, irreverent, hypocritical and disguised oaths. Yes, there is a place for lawful oaths, particularly in civil and public matters, but under ordinary circumstances, our simple word should be trustworthy and sufficient. This is what verse 37 means, “But let your communication be, Yea, yea: Nay, nay: for whatsoever is more than these cometh of evil.” Every normal word in the course of daily speech and conversation should be a truthful word – plain and unqualified as to its trustworthiness.

There are people in this world (and perhaps you have met some of them before) who do not have a very good reputation for speaking the truth, and thus they are in the habit of injecting frequent oaths into their conversations to give credibility to their words. I well remember some schoolmates of mine who were like that. One of them would often say, “Cross my heart.” Another, who was a scout, would raise his hand and say “Scout’s honour” in order to verify that he was speaking the truth.

As an aside, it is interesting that when the Scout movement first started in the early 1900s, the very first scout law states, “A SCOUT'S HONOUR IS TO BE TRUSTED. If a scout says ‘On my honour it is so,’ that means it is so, just as if he had taken a most solemn oath…If a scout were to break his honour by telling a lie, or by not carrying out an order exactly when trusted on his honour to do so, he would cease to be a scout, and must hand over his scout badge and never be allowed to wear it again.”

The problem is that when people, especially those who don’t have a good reputation for truth, say such things or use such devices frequently and under normal everyday circumstances; they tend to raise even greater suspicion. Instead of being a mark of integrity, such oaths become a mark of deceit. And instead of promoting confidence, they actually promote skepticism and distrust.

This ought never to be so for us as God’s people. Instead, let us seek to be plain, honest and faithful with our words. And let us constantly teach our children the importance of this, both in our words and especially by our examples. Let us teach them that while it is legitimate for Christians to take oaths, we may only do so in God’s name, with all honesty, and under very serious circumstances. We must never do it flippantly, insincerely and unnecessarily; and that ordinarily, a simple word from our lips should be trustworthy and adequate.