(Mat 5:33-37 ESV) “Again you have heard that it was said to those of old, ‘You shall not swear falsely, but shall perform to the Lord what you have sworn.’ 34 But I say to you, Do not take an oath at all, either by heaven, for it is the throne of God, 35 or by the earth, for it is his footstool, or by Jerusalem, for it is the city of the great King. 36 And do not take an oath by your head, for you cannot make one hair white or black. 37 Let what you say be simply ‘Yes’ or ‘No’; anything more than this comes from evil.”
How can this be so when God himself has been known to utter the occasional oath?
(Psa 132:11-12 ESV) 11 The LORD swore to David a sure oath from which he will not turn back: “One of the sons of your body I will set on your throne. 12 If your sons keep my covenant and my testimonies that I shall teach them, their sons also forever shall sit on your throne.”
(Psa 95:10-11 ESV) 10 For forty years I loathed that generation and said, “They are a people who go astray in their heart, and they have not known my ways.” 11 Therefore I swore in my wrath, “They shall not enter my rest.”
And Jesus testified under oath before the Sanhedrin —
(Mat 26:63-65 NET) 63 But Jesus was silent. The high priest said to him, “I charge you under oath by the living God, tell us if you are the Christ, the Son of God.” 64 Jesus said to him, “You have said it yourself. But I tell you, from now on you will see the Son of Man sitting at the right hand of the Power and coming on the clouds of heaven.” 65 Then the high priest tore his clothes and declared, “He has blasphemed! Why do we still need witnesses? Now you have heard the blasphemy!”
And Paul invoked the name of God in several statements — which is the taking of an oath (Rom 1:9; 2 Cor 1:23; Gal 1:20; Phil 1:8).
Obviously, taking an oath is not per se a sin. In fact, in the Torah God said,
(Lev 19:12 NET) 12 You must not swear falsely in my name, so that you do not profane the name of your God. I am the LORD.
(Deu 10:20 NET) 20 Revere the LORD your God, serve him, be loyal to him and take oaths only in his name.
So what’s going on here?
What Jesus is teaching here is not the absolute prohibition of all oaths, for then he’d be against God’s ways of dealing with our redemption, but against legal oaths that reflect distancing God from what we do in scaling our obligations. He calls his followers into kingdom realities.
Scot McKnight, Sermon on the Mount (The Story of God Bible Commentary; Accordance electronic ed. Grand Rapids: Zondervan, 2013), 118.
To the extent McKnight concludes that Jesus is revising Torah, I disagree. Rather, I think Jesus is telling us that, although swearing is allowed by the Torah, it should be unnecessary for Kingdom people because, after all, we’re all forbidden to bear false witness. It’s not that swearing is a taboo, but that swearing can lead to a double standard so that the absence of an oath makes the truth optional. And Jesus will not allow us to lie just because we aren’t under oath. Hence, there is no need for an oath in a Kingdom where lies are not allowed.
James, the brother of Jesus, writes,
(Jam 5:12 ESV) But above all, my brothers, do not swear, either by heaven or by earth or by any other oath, but let your “yes” be yes and your “no” be no, so that you may not fall under condemnation.
(Eph 4:25 ESV) Therefore, having put away falsehood, let each one of you speak the truth with his neighbor, for we are members one of another.
(Col 3:8-10 ESV) 8 But now you must put them all away: anger, wrath, malice, slander, and obscene talk from your mouth. 9 Do not lie to one another, seeing that you have put off the old self with its practices 10 and have put on the new self, which is being renewed in knowledge after the image of its creator.
Notice that Jesus condemns the sophistry of the Pharisees. They played games as to what constituted a binding oath, when anyone who is truly God’s child should not need an oath at all. Using oaths as a means of deception — swearing “by the gold in the temple” in order to later argue that this is not a true oath — was simply a clever way to use one’s religion to justify a lie.
Discussions of the relative validity of different forms of oath and vow occupied the Rabbis to the extent of filling several tractates of the Mishnah.
R. T. France, Matthew: An Introduction and Commentary (Tyndale NTC 1; IVP/Accordance electronic ed. Downers Grove: InterVarsity Press, 1985), 129.
The conclusion of the matter is that it is never necessary for Christ’s people to swear an oath before they utter the truth. Their word should always be so reliable that nothing more than a statement is needed from them. God is in all of life, and every statement is made before him.
Leon Morris, The Gospel According to Matthew (Pillar NTC; Accordance electronic ed. Grand Rapids: Eerdmans, 1992), 125.