“Do not take an oath at all,” commands Jesus (Matthew 5:34). This prohibition raises quite a few questions. Is Jesus forbidding Christians from things like swearing to tell the truth in court? To understand what Jesus is prohibiting and how to apply it in our lives we must take a closer look at this passage.
Jesus is speaking specifically to Christians, not to the whole world.
Matthew 5:1 – 7:29 contains what is known as the Sermon on the Mount. The sermon is not a set of rules or principles to live by if you want to get to heaven. It contains instructions for those who are already going to heaven because of their faith in Jesus. Jesus’ teaching in Matt. 5:34 is for Christians, describing the way they should think about and approach oaths and promises. Here is Jesus’ full illustration:
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.’ But I say to you, Do not take an oath at all, either by heaven, for it is the throne of God, or by the earth, for it is his footstool, or by Jerusalem, for it is the city of the great King. And do not take an oath by your head, for you cannot make one hair white or black. Let what you say be simply ‘Yes’ or ‘No’; anything more than this comes from evil (Matthew 5:33-37).
Let’s break down these verses. Jesus starts with a contrast:“You heard that it was said… But I say to you.” In doing this Jesus clearly communicates that when he teaches he speaks authoritatively. When he speaks he does not simply recite or explain to us what the Old Testament law says, he speaks as if he is God himself giving commands: “I say,” not “it says.”
Jesus changes the Old Testament law.
God’s law in the Old Testament allowed oaths, but Jesus changes this for Christians. First, he talks about the old teaching, “You shall not swear falsely, but shall perform to the Lord what you have sworn.” This is not a direct quote from the Old Testament but likely an allusion to Leviticus 19:12 and Deuteronomy 23:21. Next, Jesus talks about the new teaching. The new command is to not take an oath at all. Jesus gives several examples to illustrate his point. He says one should never swear by heaven, God’s throne, the earth, Jerusalem, or by their own head. What is Jesus referencing through these examples? These are all ways that a person would intensify their promises. For example, a person might swear on the Bible or their mother’s grave to show that they are really serious. In contrast to this kind of promising, Jesus teaches that a Christian should simply say “yes” or “no.” Including an oath with your promise is sinful.
Oaths should be unnecessary.
Here’s what Jesus is saying: Christians should be honest people. So honest that our word is trustworthy all on its own. Oaths are attempts to impress or awe someone with intensity or sincerity of our promise and for the believer they should be unnecessary. We hear and see kids make oaths all the time. How do we do the same as adults? Do we need to add anything to our words in order for us or others to feel they are sincere and will be kept? Jesus teaches us that such intensifying oaths are unnecessary for a Christian, we should be people who are believable without the need for anything but our word. To put it another way, Christians say what they mean and mean what they say. Christians should not equivocate, saying one thing but meaning or intending another, rather “let what you say be simply ‘Yes’ or ‘No’” (Matt. 5:37).
It is not a sin to take an oath when civil authorities ask you too.
But what does it entail for things like swearing an affidavit or taking an oath in court? Do these come from evil? These are practices which our culture has established and it is not sinful to participate in these cultural customs or expectations. What Jesus is teaching us is that we should be honest and keep our word whether or not we take some sort of culturally expected oath. If no oath is expected or required by our culture, then there is no need for us to create our own. The word of a Christian should be guarantee enough.