Jesus warns us against swearing. When most people thing of swearing, they think of bad words. They think of George Carlin’s 7 words you can’t say on television (which is not even true anymore!). People use vulgar and profane words to make them sound more forceful. They really only make them sound vulgar and profane. As Christians, our speech is to be seasoned with grace, not peppered with profanity. Vulgar language is like swearing in that it wants people to take more notice of it, but it is not the same thing as swearing.

Swearing is taking an oath. Politicians take an oath when they are sworn into office. They should be ever reminded that their obligation is to something greater than their own happiness and that of their cronies. Witnesses take an oath before they testify in court and put themselves under a higher obligation to tell the truth (judges should be reminded that they answer to a Higher Power as well). Those married in a church should remember that their vow to be faithful goes beyond a promise to their partner—those vows were made to God. There are times when an oath or vow is properly required of us and it is good thing.

Jesus is not against taking oaths in every instance. When put under oath by the high priest, Jesus answered (see Matthew 26:63). Jesus tells us not to swear oaths in order to make us sound more serious. Why do we use the words, "Honest to God," or "May lightning strike me if …" or other oaths? We want people to take us seriously. And yet even when we use such expressions, we look for ways to wiggle out of what we promised.

Jesus mentions this theme later in the gospel (see Matthew 23:16-21). There we read of those who swore oaths, but had their fingers crossed behind their back. They wanted to sign their contracts with disappearing ink so they would not have to make good on their promises and fulfill what they had agreed. They even got fancy legal experts to parse the whole thing out to say what oaths really counted and which ones did not. A vow sworn on the altar could be broken, but one sworn on the gift on the altar could not, etc. This may seem foolish and childish, but they were quite serious about it.

Jesus pointed out that they got their values all wrong. It is foolish to say that one part of the temple was more serious than another for the purpose of vows. The whole place was there for the name of God. He points out that all vows and oaths worth anything are made on the name of God. To swear by heaven is to swear by the one whose throne is there. To swear by the earth is to swear by the one who made it. To swear by your head is to swear by the one in whose image you were created. In other words, all of these oaths were made on the name of God. To swear on the name of God and not fulfill what you have sworn is to use the name of God in vain.

The third commandment tells us not to misuse the name of God. The ancient Israelites were so careful not to break this commandment that they did not even pronounce the name of God. How different from us today! God, the Lord, and Jesus Christ are names referring to the deity. We hear them all the time as throwaway words, spoken like curses. This is true profanity and yet it barely gets a blip from network sensors, or radio shows. We are so used to hearing the name of God said in vain that it is barely considered impolite anymore. Dear Christian, does it catch your ear? Does it come off your tongue?

To swear an oath or vow on the name of the Lord and not follow through is using the name of the Lord in vain. Ecclesiastes 5:4 says that God has no pleasure in foolish prattle. If you make a vow, better do it. Why should God be angry with you and destroy the work of your hands?

Jesus knows how we want people to take us seriously. He knows that we will use anything, even God’s name, to make us look more serious. He knows how we get ourselves in trouble when we do this. He has another way for us.

Jesus tells us to be plain and truthful. Be honest. Let your yes be yes and mean it. Let your no be no and mean it. If you are known as one who tells the truth, you don’t need to swear an oath in order for someone to take you seriously. Your word is known to be true and should suffice. If your word is not known to be true (or if it is known to be dubious) then you have a problem. Anything you try to do, any oath you make up, will not give you any more credibility because people will still wonder if you are crossing your fingers behind your back. Whenever we go beyond the clear truth and start to hedge things in polite or malicious games, we are on the devil’s playing field.

Here is where we need both the forgiveness of Christ to undo our sinful speech and the power of the Holy Spirit to give us truthful hearts and tongues.