Think about some of the idioms we use to stress our truthfulness or intention to keep a promise. When I was child, I used the phrase, “Scout’s Honor” even though I never belonged to the Boy Scouts. The origin of the phrase is rooted in the high standards once associated with the Boy Scouts; to use the phrase was to indicate your intention of keeping a promise or to tell the truth.
Another idiom used in association with one’s honesty is a bit on the morbid side. I am sure you have heard it before: “I swear on my mother’s grave.” Why would anyone swear on one’s mother’s grave instead of anyone else in the family? For guys, mothers are sacred in just about every culture, and to swear on your mother’s grave, is to stress the integrity and truthfulness of a statement or promise. Most men would never wish ill upon their mothers, especially upon their dead mother. Some believe that the origin of the statement is rooted in the belief that the soul of a person was still tied to the grave and to swear on your mother’s grave while lying would result in your mother’s soul being sent to hell.
I do not think I ever swore on my mother’s grave, maybe because she is still alive and it never made sense to me, but I have used another idiom that you are probably familiar with. The idiom I am referring is “Cross my heart and hope to die.” It is believed that this idiom originated in America in the mid 1900’s. Because the heart is regarded as the center of the emotions and the symbol of the cross is a reference to Jesus, to cross your heart is to attest to your honesty before Christ; that the truthfulness or intention keeping your word is bound to your life.
Another thing I did as a child to stress my truthfulness was to “pinky swear.” I was curious about its origins and where we got the practice from. To be honest, I thought it was an innocent childhood practice of locking pinkies to signify the intention of keeping a promise. But why lock pinkies? Apparently, you do it to signify that if the person who made the promise breaks his/her promise, then the other can break that person’s pinky. In the late 1800’s some children would lock pinkies and then repeat the words:
Whoever tells a lie
Will sink down to the bad place
And never rise up again.
The little statement above is not the worst of it. The origins of pinky swearing can be traced all the way back to the 1600’s and was called yubikiri, which literally means “finger cut-off.” So, I guess that if you made a pinky promise in Japan in the 1600’s and broke that promise, your finger would not be broken, but chopped off.
Today, we come to the fourth “You have heard that it was said…” statement that is tied to the righteousness of the scribes and Pharisees (see Matt. 5:17-20). Each of the “you have heard that it was said” statements so far served to correct a mischaracterization of what the Ten Commandments and the rest of the Law in the Old Testament really meant. When it came to honoring the name of the LORD (the 3rd Commandment) and lying (the 9th Commandment) the scribes and Pharisees believed they did a good job in obeying those commands. It is here that Jesus uncovers the heart of their problem:
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)
What is an Oath?
According to dictionary, an oath is a “solemn promise” that often invoked a divine witness, and in the case of the Hebrew people, when they made a vow, they would often invoke the name of Yahweh. Oaths are a part of our dealings. Oaths are taken when sworn into services of various kinds. Oaths are also taken before giving one’s testimony in court. Oaths come in the form of verbal commitments as well as written contractual agreements. Oaths are the strongest of pledges that a promise will be kept or one’s word is to be trusted.
Vows and oaths were not just given and taken among God’s people, but God allowed them; he provided instructions how his people were to make and keep them: “If a man vows a vow to the LORD, or swears an oath to bind himself by a pledge, he shall not break his word. He shall do according to all that proceeds out of his mouth” (Numbers 30:2). God also warned his people to not carelessly make vows or oaths: “You shall not swear by my name falsely, and so profane the name of your God: I am the Lord” (Leviticus 19:12).
God also made vows and gave oaths, and he still does so today. After God flooded the earth, he vowed that he would never flood the earth again (Gen. 9:8-11). God vowed to bless Abraham: “And the angel of the Lord called to Abraham a second time from heaven and said, “By myself I have sworn, declares the Lord, because you have done this and have not withheld your son, your only son, I will surely bless you, and I will surely multiply your offspring as the stars of heaven and as the sand that is on the seashore. And your offspring shall possess the gate of his enemies…” (Genesis 22:15–17). God also swore that he would send a redeemer to rescue sin-cursed humans (see Ps. 132:11; Luke 1:68-79). However, unlike mankind, God did not and does not make vows and take oaths to increase his credibility but to reaffirm our confidence in a world full of broken promises.
God does not bind himself to a vow or oath because he cannot be trusted, he does it to elicit and confirm our faith. We, on the other hand, bind ourselves to a vow or oath because doing so binds us to faithfulness while it is much easier to be faithless. Daniel Doriani, in his commentary on the Gospel of Matthew said we ask for vows, oaths, and promises as a testimony against the faithlessness of mankind. Here is what Doriani observed: “The very request for a promise testifies that we are not reliable…. The very existence of customs such as oaths and promises reveal that human life is tainted by deception.”
Was Jesus Against Oaths?
So, was Jesus against oaths? Not all oaths. I know this because in Matthew 26:63 the high priest demanded of Jesus to answer under oath, “I adjure you by the living God, tell us if you are the Christ, the Son of God.” Jesus did not correct the high priest for using the language he used because he did not need to correct him for invoking the name of God so that Jesus would answer truthfully; in fact, Jesus answered: “You have said so. But I tell you, from now on you will see the Son of Man seated at the right had of Power and coming on the clouds of heaven” (v. 64). What Jesus was against was the same thing God prohibited his people from doing, and that was to swear by his name in regards to trivial matters and to do so with no intention of keeping their vows, oaths, and promises.
What Jesus was against was the way the scribes and Pharisees twisted the Mosaic Law for their own fame and reputation. They did this by priding themselves on not physically committing adultery, but they twisted the scriptures to make it easy to divorce their wives so they could marry whoever they were lusting after. They manipulated the Old Testament Law in such a way that it made themselves look good in the eyes of others, but Jesus saw right through their hypocrisy.
When it came to the ninth commandment, they developed an elaborate system that allowed them to take vows without the need to keep all their vows. The Pharisees and scribes believed that they were bound to a promise based on how they vowed or took an oath; this is something Jesus exposed. If they swore by Jerusalem, their vow was not binding, but if they swore toward Jerusalem, their vow was binding. If a person swore by the temple, then the vow was not binding, but if a person swore by the gold of the temple, their vow was binding. In other words, the religious and pious scribes and Pharisees manipulated the Word of God by reducing the commandments of God to something that worked in their favor. Again, Daniel Doriani’s insights are helpful here: “The rabbinic teaching perverted the purpose of oaths. Instead of calling on God to assure honesty, oaths were phrased so to avoid God’s punishment when speaking dishonestly.
By twisting the Word of God so that they could sin against God and others, they were also guilty of taking the name of the LORD in vain, and thus breaking the third commandment in an effort to pervert the ninth commandment. This is why Jesus continued: “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 5:34–37). Later, and not many days before Jesus was handed over to be crucified, he called out the hypocrisy of the scribes and Pharisees for the way they treated the Law of God:
“Woe to you, blind guides, who say, ‘If anyone swears by the temple, it is nothing, but if anyone swears by the gold of the temple, he is bound by his oath.’ You blind fools! For which is greater, the gold or the temple that has made the gold sacred? And you say, ‘If anyone swears by the altar, it is nothing, but if anyone swears by the gift that is on the altar, he is bound by his oath.’ You blind men! For which is greater, the gift or the altar that makes the gift sacred? So whoever swears by the altar swears by it and by everything on it. And whoever swears by the temple swears by it and by him who dwells in it. And whoever swears by heaven swears by the throne of God and by him who sits upon it.” (Matthew 23:16–22)
Based on what Jesus said in verses 34-37, he was not against all oaths but only the ones that misused the name of God and made the one giving the oath a liar. It is arrogant to assume that there are some things God rules over and some things he does not rule over, or to assume that he sees certain behaviors and not others. We treat God the way a child playfully treats his or her parents in playing “Hide and Go Seek”; just because your child covered his or her eyes did not mean that they were out of sight from mom or dad. Yet, we humans foolishly act in the same manner before a God who sees all things. God created it all, therefore he owns it all… including the hairs on your head. So, to swear by anything is to invoke the name of the one who already owns it, and we live in a world which arrogantly vows, promises, and takes oaths that inevitably makes our world a place full of deception where God’s name is profaned. This is the world Jesus has called us out of for the purpose of living a better way.
What Kind of People Ought We to Be?
So, what kind of people ought the Christian to be? Before I answer, permit me to provide a corrective on our understanding of the third commandment: “You shall not take the name of the Lord your God in vain, for the Lord will not hold him guiltless who takes his name in vain” (Exodus 20:7). It is assumed by both those within the Church and outside the Church that to take the LORD’s name in vain is solely based on what comes out of our mouths or what we put in print, but that is not the only way we misuse the name of Yahweh.
There is a reason why it is impossible for the animal kingdom, the mountains, the oceans, the trees, the planets, stars, and galaxies to take the name of the LORD in vain. The reason why human beings are the only creature capable of taking the name of the LORD in vain is that we were created and are born as the only creature that bears the image of God. Every sin that we commit is a breaking of the third commandment because to use our bodies in any way to sin against God is to misuse his name. Now, think of the multitude of ways we take the name of the LORD in vain.
The way that Jesus calls us to follow is a way that leads us to the place we were made for. It is the way where our worship is realigned so that it is no longer me at the center but God. Jesus’ way leads us out of darkness and into his marvelous light, just as we are reminded by the apostle Peter: “But you are a chosen race, a royal priesthood, a holy nation, a people for his own possession, that you may proclaim the excellencies of him who called you out of darkness into his marvelous light. Once you were not a people, but now you are God’s people; once you had not received mercy, but now you have received mercy” (1 Peter 2:9–10).
Jesus is not forbidding the Christian from taking oaths, he is telling us that unlike the scribes and Pharisees, we follow a Savior who is, “the Way, and the Truth, and the Life.” As followers of Jesus, we ought to be so known by our truthfulness that the need for vows and oaths in a world full of evil is not necessary because the culture and character of our lives have been so shaped by Jesus that our “Yes” and our “No” is enough.
But here is the rub: We still fall short. Our “yes” is not the “yes” that it ought to be and our “no” is not the “no” that it ought to be. Our lives may better reflect the character of a holy God since coming to Jesus, but our lives do not consistently reflect holiness. The call of God, “You shall be holy, for I am holy” (1 Pet. 1:15-16; Lev. 11:44) often seems just beyond our reach, doesn’t it? We bend and twist God’s word, we make promises we do not keep, we make commitments we never intended to keep, or at best, hoped to keep but didn’t. Jesus’ words in his sermon stand against us in that they show us that we too are guilty, so again we are haunted by what he said earlier in his sermon: “For I tell you, unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven” (v. 20).
The only way our righteousness can ever exceed the righteousness of the scribes and Pharisees is that we find our righteousness in Jesus. What I hope you are seeing in the Sermon on the Mount is that Jesus the preacher leads us to Jesus the Savior! If we come to him as our savior, he promises that he will change us and mold us into something much more beautiful. He will make us new (see 2 Cor. 5:16-21).
 Bartlett’s Dictionary of Americanisms. googlebooks. 1860. Retrieved 2013-05-25.
 Daniel M. Doriani. Reformed Expository Commentary (Phillipsburg, NJ: P&R Publishing; 2008), p. 168.
 Daniel M. Doriani. ESV Expository Commentary: Matthew – Luke (Wheaton, IL: Crossway; 2021), p. 98.
 One could make the case that the demons take the name of the LORD in vain, but if they do, they can only do so in word only because they do not bear the image of God.