MATTHEW 5:33-37 - Swear Like A Christian

Introduction

So, let’s start off this morning with a little mental exercise—see if you can finish these well-known sayings: “Cross my heart and… (hope to die, stick a needle in my eye)”

"I swear on my… (mother’s grave)”

"I’m not gonna… (lie)”

“As God is my .... (witness)”

There are all kinds of ways that people insist that they are telling the truth in our day, aren’t there? From “cross my heart and hope to die” to blue-checks on Twitter accounts to fights over “fake news” to the concern over sophisticated AI-generated “deepfakes”, we are a people who are desperate for assurance that they aren’t being lied to. Because we are also a people who know how to shade the truth, massage the facts, split the hairs, spin the narrative. The proliferation of oaths and contracts and “blue-checks” and two-factor authentication is a demonstration that we are a people who can’t be trusted to tell the truth.

In our text this morning, Jesus is continuing His disputations with the religious leaders of the day, the scribes and Pharisees. They had reduced righteousness before God down to a matter of outward behavior—as long as you do this or don’t do that, you are righteous before God. Hate is fine as long as you don’t actually murder someone. Lust is fine as long as you don’t actually commit adultery. Divorce is fine as long as you file all the appropriate paperwork. But in His Sermon on the Mount, Jesus is inaugurating a righteousness that surpasses the righteousness of the scribes and Pharisees—not a righteousness based on more and better lawkeeping, but a righteousness that comes from a complete regeneration of your heart: a whole new way of being human through the New Birth that He offers through the Gospel.

So as we examine Jesus’ words about oaths and vows in these verses, what I want to get at is that because the New Birth gives you a whole new relationship with God, it therefore gives you a whole new relationship with the truth. So let us put it like this:

When Christ is your SAVIOR, the truth is your FRIEND

The New Birth gives you a new relationship with the Truth—because it gives you a new relationship with Christ, who is the Truth. And so

I. You have CONFIDENCE in your WORDS before GOD (Matthew 5:33; cp. Psalm 139:23-24)

When you have come to God through faith in Christ, you have a new relationship with Him—not a relationship based on your performance of good works out of fear of judgment, but a relationship based on the good works of Christ that is characterized by His love for you. You have nothing to hide from God; you can pray along with the psalmist in Psalm 139--

Psalm 139:23–24 (LSB)

23 Search me, O God, and know my heart; Try me and know my anxious thoughts; 24 And see if there be any hurtful way in me, And lead me in the everlasting way.

You have the same confidence before God that the Apostle Paul did when he swore an oath to the church in Rome:

Romans 1:9 (LSB)

9 For God, whom I serve in my spirit in the gospel of His Son, is my witness as to how without ceasing I make mention of you,

Because of the Gospel, because he lived in right relationship with the Paul could call God as his witness—he could swear an oath to the believers in Rome—that he prayed for them constantly. This helps us to see—and I think it is good to establish right off the bat—that

Not all OATHS are FORBIDDEN

This is an important distinction, because at first glance, Jesus’ teaching here seems to prohibit all swearing of vows:

Matthew 5:33–34 (LSB)

33 “Again, you have heard that the ancients were told, ‘YOU SHALL NOT MAKE FALSE VOWS, BUT SHALL FULFILL YOUR VOWS TO THE LORD.’ 34 “But I say to you, make no oath at all...

But as we have seen, the Apostle Paul swears by God’s Name that he prayed constantly for the Romans—and he says something similar to the church in Corinth:

2 Corinthians 1:23 (LSB)

23 But I call God as witness to my soul, that to spare you I did not come again to Corinth.

In fact, in the Old Testament, God’s people are commanded to take oaths in YHWH’s Name:

Deuteronomy 6:13 (LSB)

13 “Yahweh your God you shall fear; and Him you shall serve; and by His name you shall swear.

And God Himself swore an oath by His own Name when He blessed Abraham for his faith in sacrificing his son Isaac:

Genesis 22:16–17 (LSB)

16 and said, “By Myself I have sworn, declares Yahweh, because you have done this thing and have not spared your son, your only one, 17 indeed I will greatly bless you, and I will greatly multiply your seed...

We even see Jesus Himself responding to being put under oath by Caiaphas at His trial in Matthew 26:63-64:

Matthew 26:63–64 (LSB)

63 But Jesus kept silent. And the high priest said to Him, “I put You under oath by the living God, that You tell us whether You are the Christ, the Son of God.” 64 Jesus said to him, “You yourself said it; nevertheless I tell you, hereafter you will see THE SON OF MAN SITTING AT THE RIGHT HAND OF POWER and COMING ON THE CLOUDS OF HEAVEN.”

The pattern of Scripture shows us that an oath—calling on God to witness the truth of your words—is lawful when the truth is on your side. When you are speaking truth and you know you are speaking the truth, it is not a sin to call God to witness your truthfulness.

So why does Jesus say, “Make no oath at all...” in Matthew 5:34? In the context of the rest of the Scriptures we must not take Jesus’ words to mean that any oath is sinful. Not every oath is forbidden in Scripture, but at the same time

Every OATH has CONSEQUENCES (cp. Exodus 20:7; Numbers 30:2)

We will unpack a bit more of what Jesus is warning against as we go through the rest of this passage, but at this point consider for a moment what you are doing when you say things like “I swear to God” or “As God is my witness”. When you say such things in order to demonstrate your truthfulness, you are inviting the judgment of God on yourself. Moses makes this clear in Leviticus 19:12

Leviticus 19:12 (LSB)

12 ‘And you shall not swear falsely by My name, so as to profane the name of your God; I am Yahweh.

and in Numbers 30:2:

Numbers 30:2 (LSB)

2 “If a man makes a vow to Yahweh or swears an oath to bind himself with a binding obligation, he shall not violate his word; he shall do according to all that proceeds out of his mouth.

Calling God to be your witness when you are lying—whether you know you are lying or whether you think you’re telling the truth—is the very definition of taking His Name in vain:

Exodus 20:7 (LSB)

7 “You shall not take the name of Yahweh your God in vain, for Yahweh will not leave him unpunished who takes His name in vain.

Jesus’ advice in Matthew 5:34 is a reflection of something very similar that Moses said in Deuteronomy 23:21-22:

Deuteronomy 23:21–22 (LSB)

21 “When you make a vow to Yahweh your God, you shall not delay to pay it, for Yahweh your God will surely require it of you; and it will be a sin in you. 22 “However, if you refrain from vowing, it will not be a sin in you.

Not all oaths are forbidden, but every oath has consequences, because they are made before the sight of God who sees everything (including the very depths of your heart), who knows everything (including all your motives and reasons for swearing in His Name) and who is powerful to visit the consequences of a false vow on you. And so, Jesus says, it is better not to vow at all rather than risk the consequences of taking God’s Name in vain with a false oath, or by swearing to do something that you do not do.

But when the truth is your friend—when you are in a right relationship with the Truth by faith in Jesus Christ—then you have confidence in your words before God. You are able to know the truth, you are able to love the truth, you are able to speak the truth with a freedom that can only come through the New Birth.

And that means that, when it comes to the truth,

II. You don’t need to HIDE behind TECHNICALITIES (Matthew 5:34-36, cp. Matthew 23:16-22)

In verses 34-36, Jesus goes on to call out the way the scribes and Pharisees (and others) were swearing to their truthfulness:

Matthew 5:34–36 (LSB)

34 “But I say to you, make no oath at all, either by heaven, for it is the throne of God, 35 or by the earth, for it is the footstool of His feet, or by Jerusalem, for it is THE CITY OF THE GREAT KING. 36 “Nor shall you make an oath by your head, for you cannot make one hair white or black.

In Jesus’ day in first-century Israel, the whole practice of taking oaths had been greatly abused—people had created ways to take an oath that almost used Yahweh’s Name, but didn’t quite do so. They always had “plausible deniability”. They could “swear” that they were truthful, or take a “vow” that they would keep their promise, but they did it in such a way that, if necessary, they could claim that they didn’t really take an oath after all...

When the truth is not your friend, you will always have to find ways around it—anyone remember Bill Clinton’s howler when he insisted that he really didn’t commit perjury “because it depends on what the definition of ‘is’ is...”? Jesus warns that trying to hide behind technicalities doesn’t work. In Matthew 23:16-18 He warns His listeners,

Don’t settle for the APPEARANCE of truthfulness (Matt. 23:16-22)

Matthew 23:16–19 (LSB)

16 “Woe to you, blind guides, who say, ‘Whoever swears by the sanctuary, that is nothing; but whoever swears by the gold of the sanctuary is obligated.’ 17 “You fools and blind men! For which is more important, the gold or the sanctuary that sanctified the gold? 18 “And, ‘Whoever swears by the altar, that is nothing, but whoever swears by the offering on it, he is obligated.’ 19 “You blind men, which is more important, the offering, or the altar that sanctifies the offering?

When it comes to telling the truth before God, Jesus warns, God does not honor technicalities!

When Christ is your Savior, the truth is your friend—don’t settle for the appearance of truthfulness. And in the same way, if the truth is your friend

Don’t use the TRUTH to tell a LIE

Like the first-century inhabitants of Israel in Jesus’ day, we have a lot of ways of sounding like we’re telling the truth, but actually lying. We know how to say something that is technically true, but still communicates a falsehood. For instance, if one of my Penn State students came to church and said, “CSF was great on Wednesday, Tharren showed up sober this week!”—that would be the truth, but it would communicate a lie. Or saying, “Yes, I went shopping yesterday; I went to Wal-Mart and got groceries”—twenty dollars worth of groceries and a hundred dollars worth of other things you didn’t need and don’t want to talk about. Or “I wasn’t home last night because I went to the library to study”—for a half hour, then you went out and partied the rest of the night.

When the truth is your friend, you don’t use it to tell a lie. You don’t hide behind technicalities, you don’t find ways to weasel out of being honest with your words. Jesus tells us in verse 37 of our text that the new way of being human that He is establishing in the New Birth means that

III. You don’t need to INSIST your words are HONEST (Matthew 5:37)

Matthew 5:37 (LSB)

37 “But let your statement be, ‘Yes, yes’ or ‘No, no’; anything beyond these is of the evil one.

Because Christ is your Savior, Christian, the truth is your Friend—Christ Himself is “the way, the Truth, and the Life” (John 14:6). You are not just a friend of the Truth; you belong to the Truth. And that means that you are not meant to be constantly affirming your statements with “I swear to God”, or “I’m not lying” or “Cross my heart and hope to die...” If you are a Friend of Christ through His saving work, then you are a Friend of Truth Himself. And that means that, in the old manner of speaking,

Your word is your BOND

If you have to constantly swear that you’re telling the truth, what are you really communicating? That you can’t be trusted! A “Yes” from you should be simply unquestioned by everyone who hears it, and a no from you should be the end of the matter. You say you will be there Saturday morning to help your buddy move into his new apartment, and he can relax, knowing you will be there. You tell your child “No, you can’t have a snack, we’re almost ready to eat”, and she knows better than to ask you again, because she knows that when you say “No”, it means… No!

This is the mark of a friend of the Truth—the mark of one who belongs to Jesus Christ by faith. He is the Word that speaks the Truth about God, and so your word has the reputation of being true.

And so how do you develop that reputation for truth? How do you go about cultivating that kind of trust in your word, that when you say yes, you mean it? Turn with me to Psalm 15 (p. 453 in the pew Bible)—there is an example here that everyone who wants to cultivate this kind of friendship with the truth must emulate.

Psalm 15 is David’s song about the character of a godly man—a man who is righteous in the sight of God. Notice how prominently truth figures in this man’s life:

Psalm 15:1–3 (LSB)

1 O Yahweh, who may sojourn in Your tent? Who may dwell on Your holy mountain? 2 He who walks blamelessly, and works righteousness, And speaks truth in his heart. 3 He does not slander with his tongue, Nor does evil to his neighbor, Nor takes up a reproach against his friend;

This is a portrait of a man for whom truth is a friend. And there is a particular relationship to the truth that David sings about in verse 4:

Psalm 15:4 (LSB)

4 In whose eyes a reprobate is despised, But who honors those who fear Yahweh; He swears to his own hurt and does not change;

Your “yes” will be “yes” and your “no” will be “no” when

You keep PROMISES even when they HURT (cp. Psalm 15:4)

One of the most frustrating aspects of belonging to a people who are not friends with truth is how easily we break our word when it becomes inconvenient to keep. We back out of our word when we find out that keeping it will cost us more than we expected; we figure people will just “understand” that we had no choice. “I know I said I would show up and help with that work project, but I realized that had a ticket to the football game—I spent a lot of money on that ticket; they’ll understand...” Sure—they’ll “understand”: They’ll understand that you break your word when it inconveniences you. And the next time you “promise” something, you’ll have to “swear” that you will do what you promised.

When you belong to Christ by faith through the New Birth, you have a new relationship with the Truth, because you belong to Truth Himself. And the author of Hebrews tells us that when Christ came to earth, He gave His word that He would do what His Father sent Him to do:

Hebrews 10:5–7 (LSB)

5 Therefore, when He comes into the world, He says, “SACRIFICE AND OFFERING YOU HAVE NOT DESIRED, BUT A BODY YOU HAVE PREPARED FOR ME; 6 IN BURNT OFFERINGS AND sacrifices FOR SIN YOU HAVE TAKEN NO PLEASURE. 7 “THEN I SAID, ‘BEHOLD, I HAVE COME, IN THE SCROLL OF THE BOOK IT IS WRITTEN OF ME, TO DO YOUR WILL, O GOD.’”

And on the night before He went to that Cross, beloved, Jesus struggled in the Garden of Gethsemane with the consequences of the vow He had made, in agony crying out to His Father, His sweat like drops of blood falling on the ground:

Luke 22:41–42 (LSB)

41 And He withdrew from them about a stone’s throw, and He knelt down and began to pray, 42 saying, “Father, if You are willing, remove this cup from Me, yet not My will, but Yours be done.”

Christian—where would you be now if He had cut and run that night? Where would you be if He had said, “No—this promise costs me too much to keep; surely My Father will understand—there has to be another way...”

But your Savior kept His vow:

Hebrews 10:9–10 (LSB)

9 then He said, “BEHOLD, I HAVE COME TO DO YOUR WILL.” He takes away the first in order to establish the second. 10 By this will we have been sanctified through the offering of the body of Jesus Christ once for all.

For all of the lies you told this week—all of the half-truths, all of the evasions, all of the times you used God’s Name to convince someone you weren’t lying, every time you deliberately let someone else misunderstand you, every project you turned in that was actually someone else’s work, every promise you broke because you realized you had something better to do. When you take stock of your trustworthiness, do you realize that no one has any reason to believe you will do what you say, that you are always looking for loopholes in what you have promised, that the reason you don’t feel like you can trust others to keep their word is because you never keep your own word.

For all of the ways that you have lied, all the ways you have been lied to, for all the ways you have used your identity as a “Christian” to get people to trust your promises when they really shouldn’t have—your only hope before a righteous God is that there was a Man who kept His Promise! For all your failures of truth, all your broken bonds, all your lies and evasions, Christ is the Truth who died for your lies; He kept His word even though it meant His agony; the truth is your friend because Truth Himself died on that Cross.

And not only did He redeem you because He kept His promise to His Father, but He will keep His promise to deliver you safe to the glory of His Father!

John 10:27–28 (LSB)

27 “My sheep hear My voice, and I know them, and they follow Me; 28 and I give eternal life to them, and they will never perish—ever; and no one will snatch them out of My hand.

Your treacheries and lies and broken words are atoned for because He kept His promise; your future glory and eternal hope is guaranteed because He will never break His promise. So come to Him with all of your lies and all of your broken promises and all of your false vows; throw yourself on the mercy of the One who never broke a promise; who not only tells the truth, but is Truth Himself—your Savior, Jesus Christ!

BENEDICTION:

1 Thessalonians 5:23–24 (LSB)

23 Now may the God of peace Himself sanctify you entirely, and may your spirit and soul and body be preserved complete, without blame at the coming of our Lord Jesus Christ. 24 Faithful is He who calls you, who also will do it.... 28 The grace of our Lord Jesus Christ be with you. Amen.

QUESTIONS FOR REFLECTION:

Why does our culture have so many different ways of insisting that our words are true and trustworthy? What does this say about the day and age in which we live?

Read John 14:6. How does this verse establish the statement, “When Christ is your Savior, the truth is your friend”? How is a Christian’s relationship with Truth different from an unbeliever?

What does it mean to “settle for the appearance of truthfulness”? How did the so-called “oaths” that people used in Jesus’ day compare with the way we try to “look” truthful today?

Think about a time you allowed a true statement to give a false or misleading impression to someone? Why did you do it? What would have been different had you not allowed that lie to stand?

Read Psalm 15 again. What are some examples of “swearing to your own hurt”? How does keeping your word in situations like this demonstrate that your promises and vows are trustworthy?