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SM #22: Sanctifying Speech

Again, you have heard that it was said to the ancient ones, ‘Do not break your oath, but fulfill to the Lord the vows you have made.’ But I tell you, do not swear an oath at all: either by heaven, for it is God’s throne; or by the earth, for it is his footstool; or by Jerusalem, for it is the city of the Great King. And do not swear by your head, for you cannot make even one hair white or black. But simply let your ‘Yes’ mean ‘Yes’ and ‘No’ mean ‘No’; anything beyond this comes from the evil one. ~ JESUS (Matthew 5:33-37)


SUMMARY: Read this and skip the rest (if you want)

  • We have arrived at the fourth out of six case studies in how to read the Bible. Here we see Jesus definitively and authoritatively changing a biblical practice for God's people.

  • Swearing oaths was clearly allowed and even commanded in the Torah.

  • Both the Old Testament and New Testament promote a high value of truth-telling, just in different ways.

  • Now that Jesus is ushering in his new way, returning to the old ways is "evil".

  • Jesus is relocating all religious authority from Scripture to himself.

  • Christians interpret and apply this teaching of Jesus differently. But we all should apply it somehow.

  • From this passage, Anabaptists derive the idea of "plain speech" - talking simply, directly, and truthfully at all times, minus an overuse of embellishments, exaggerations, or sarcasm that might be used to confuse or hide the plain truth.

  • Two key takeaways: 1) Since we know THE truth personally (John 14:6), disciples of Jesus value truth in all our interactions; 2) Jesus overrules (literally takes authority over) the old ways of the Old Covenant. Therefore Christ-followers do not just "follow the Bible" - we read the Bible so we can follow Jesus.

CORE (The heart of the message)

Truth spoken in love should be the national language of the Kingdom of Christ. There is no going back to the way of law, even God's law, after the gospel of grace has done its work.

CONTEXT (What’s going on before and after this passage)

This is the fourth of the Six Antitheses - six illustrations or case studies that demonstrate the contrast between Old Covenant righteousness and New Covenant righteousness. Through these examples, Jesus is teaching us how to read our own Bibles with Jesus as our ultimate authority and interpreter.

Swearing an oath to tell the truth or making a vow to do something has been a part of all human societies. (Oaths, vows, and promises are overlapping realities and most people use the words interchangeably. Promises are more popular between people in daily life whereas vows and oaths usually carry a more official, religious, or legal weight.)

In the Bible, God repeatedly swears oaths to the truthfulness of his promises (e.g., Genesis 9:8-17; 22:16-17; Psalm 95:11; 119:106; 132:11; Luke 1:68, 73; Acts 2:17-31; Hebrews 6:17), not because he sometimes lies otherwise, but in order to help people believe.

Because God wanted to make the unchanging nature of his purpose very clear to the heirs of what was promised, he confirmed it with an oath. ~ (Hebrews 6:17)

Covenants themselves, like the Old and New Covenants, are a kind of oath-based relationship - a commitment to live a certain way in harmony together.

So in the Old Testament Law, God is against people swearing falsely in his name (Exodus 20:7; Leviticus 6:3-5; 19:12) or swearing by a false god (Psalm 24:4), but not against swearing oaths all together. God not only allowed for oaths and vows (Numbers 30:1-16; Deuteronomy 6:13; 10:20; 23:21-23; Psalm 50:14; Ecclesiastes 5:4), he sometimes required them (Exodus 22:11; Numbers 5:19; 6:1-2).

Again to be clear: God made vows, allowed his people to make vows, regulated how vows and oaths should be used, and sometimes commanded they be used.

This biblical history of oaths and promises makes a stunning backdrop for Jesus' shocking prohibition against oath-taking. For Jesus to forbid oaths and vows all together is to set his own authority over the Bible itself. Jesus is declaring with scandalous clarity that a new Kingdom is at hand and a New Covenant - the last Covenant of covenants - has come.

Both the Old Testament and the New Testament are promoting the same high value of truth (e.g., Exodus 23:1-3; Zechariah 8:16-17; 1 Corinthians 13:6; Ephesians 4:15, 25), but now that the New Covenant has come the way we promote truth changes. Under the Old Covenant, vows and oaths helped God's people tell the truth. Under the New Covenant, the Holy Spirit - the Spirit of truth (John 14:17; 15:26; 16:13)! - guides our mouths and our consciences. A return to the way of law is to ignore the gift of the Spirit.

Love does not delight in evil but rejoices with the truth. ~ The apostle Paul (1 Corinthians 13:6)

CONSIDER (Observations about the passage)

Again. This word indicates the start of a new set of three case studies. Jesus seems to structure his illustrations of real righteousness into two groups of three. In these final three illustrations of a righteousness that goes above and beyond typical religious righteousness, their role as "antitheses" - direct abrogations or undoings - of the Old Covenant law becomes more overt.

You have heard. Not "You have read". This reminds us that most of Jesus' audience were unable to read. And even if they were literate, they would not have had access to their own copy of the Scriptures, but heard them read at their local synagogue. Personal Bible study is a modern invention. Community learning is the historical norm.

Ancient ones. Jesus is clearly making a contrast with the old ways given to the Old Covenant people, and his new way of the New Covenant. That was then, this is now.

Swearing Oaths. Jesus is referencing and contrasting clear scriptural teaching (see "Context" above). He is not directly quoting any one scriptural command but accurately summarizing many. At the time of Jesus, oath-swearing had become a verbal artform. Oaths or vows were serious promises used as verbal guarantees that someone was telling the truth and would do what they said they would do. Today we swear oaths of truth-telling in courts, oaths of loyalty in marriage and military, and we make promises whenever we want to be taken especially seriously about a commitment ("Do you promise?" "Yes! I swear!"). We might not swear by God, but we may swear by Google ("I'm telling the truth! Google it!"). Some Christians argue that signing contracts in business and banking today is also the equivalent of swearing oaths in Jesus' day. (More on this below.)

But I say to you. Jesus has just referenced Scripture and then follows it up with the word no one could have anticipated: "But". This is one of the biggest buts in the Bible. And Jesus says this based on no other authority except himself. It is Jesus' ultimate "Because I say so." In fact, the "I" (Greek, egó) may be the single most important word in this passage. The word order in the Greek text puts "I" first - "I however say to you" - which is a writing technique to put emphasis on the "I". Jesus is relocating all religious and ethical authority from Scripture to himself! Jesus is bursting the borders of biblical authority. Later Jesus will say "All authority is given to ME" - not to Scripture (Matthew 28:18). No wonder by the end of his sermon the crowd is amazed at how Jesus teaches "with authority", unlike any human teachers (Matthew 7:28-29). Rabbis then and pastors now all derive a secondary authority only to the extent that they base their teaching on Scripture. Even biblical prophets, who speak directly on behalf of God, also manifest a secondary authority by saying "Thus saith the Lord!" (The prophet Jeremiah never said, "This is true because I say so! I'm Jeremiah!) Only Jesus holds primary authority within himself, saying, not "Thus saith the Lord" but "Thus saith ME!" In other words, "This is true because I say so, period." Hey Jesus! Who do you think you are - God?!

At all. Jesus' prohibition of swearing oaths is complete and all encompassing. The Greek word here is holós, the root of our English word "whole". It means just that - the whole or complete amount of something, without exception.

Heaven / Earth / Jerusalem / Head. Jesus uses multiple examples of truth-marking: verbal embellishments we use to engender trust in our words. He does this again in his rebuke to the religious leaders in 23:16-22, pointing out the silliness of this kind of verbal virtue-signalling. The Tradition of the Elders at the time of Jesus (later recorded in the Mishnah) included an incredible complexity of instructions for making binding vs non-binding oaths (e.g., swearing by Jerusalem was not binding, but swearing toward Jerusalem was). A legalistic use of Scripture always eventually degenerates into a loophole mentality. Notice that Jesus refers to Jerusalem as "the city of the Great King" at a time where there was no authoritative king ruling but rather a Roman procurator, Pontius Pilate. Jesus may be foreshadowing the true king's future entrance on a donkey.

Yes / No. The Greek is literally, "Let your words be yes yes and no no." Kingdom people should not have to use verbal formulas to distinguish our totally true and trustworthy words from our mostly true and trustworthy words.

The Evil One. This Greek word can be personal or general, that is "the evil one" or just "evil". Most translators believe the construct here is personal. But either way, Jesus says something shocking: diluting plain honesty through vow-making comes from an evil origin - the father of lies no less (John 8:44)! This is one of the most challenging statements in the entire Sermon on the Mount, since Jesus is referring to a biblical command as being "evil" if practiced in his new Kingdom of the Heavens on earth. Our Teacher has some explaining to do.

"It must be frankly admitted that here Jesus formally contravenes OT law. What it permits or commands, he forbids." ~ D.A. Carson (The Expositor's Bible Commentary)

CONFESSION (Personal reflection)

I confess that my adultery is only part of my great failure. I have, for a season of my life, also become good at lying.

As we have all heard, one sin leads to another, and in order to conceal certain sins we lie. People who commit adultery will also lie, and not only to everyone around them. We often lie to ourselves, unable to consciously confront our own sin. We call this self-lying denial.

There is a line in the Parable of the Prodigal Son where it says the wayward son's repentance started "when he came to himself" (a literal translation of Luke 15:17). I know that moment intimately.

Sometimes our sin and the lies we tell ourselves so we can continue in sin will cleave our souls in two. Unable to endure the cognitive dissonance, this is what happened to me. When I was first confronted, I experienced a reunion of sorts, when both halves of me where able to exist in the same room at the same time. I "came to myself". It was painful beyond belief, like a kind of soul surgery for which there is no anaesthetic. But somehow in the middle of the torment, I was aware that this was the beginning of my healing journey toward wholeness.

This is the meaning of integrity, to have all our divided parts integrated. It comes from the Latin integratas, meaning whole and undivided.

Another word with Latin roots I've come to value is sincere, from the Latin sine cere, meaning "without wax". In Roman times, if a clay pot or marble sculpture cracked in the creation process, dishonest artisans might cover the flaws by melting wax into the fissures. So honest sculptors would sometimes present their work as being "sine cera" or "without wax".

Jesus wants his disciples to be "without wax" at all times. But for those of us with serious flaws already, the temptation to hide our cracks with the wax of denial and deception will be powerful.

Physically, we naturally recoil to avoid pain. If something is too hot to the touch, we pull away quickly and automatically. We don't have to think about it; we don't have to weigh the pros and cons to make a conscious decision. We simply experience a "somatic reflex". And psychologically, if one part of our lives is potentially too painful to acknowledge, if we perceive the truth itself as too hurtful to admit, the rest of our psyche may reflexively pull away. Different parts of our psyche will separate for safety. We dis-integrate.

The 1985 movie King David, starring Richard Gere, is a biblical B movie with some powerful and meaningful moments. When seeing it again recently I watched with new eyes the scene where Nathan the prophet confronts David about his sin. It felt as though I was watching the internal reintegration of King David's soul - and the accompanying pain. Denial is stripped away with the words "Thou art the man" (see 2 Samuel 12).

The pain is thorough. There is no anesthetic for this kind of surgery.

The moment King David comes to himself.

In my life, it was the lying as much as the adultery that fractured my soul. I have always valued truth and honesty as tools to foster intimacy and loving community. Every time I twisted truth to cover my tracks, something died inside me and around me, since my connection in loving community was being fractured, lie by lie.

But now, suddenly, I am pulled into the middle of the most intimate, loving, gracious, truth-full and trusting experience of community I have ever had. Gathering together with (or better, being gathered up into) a small group of righteous (that is, rightly-related) sisters and brothers is healing like nothing else. Turns out, when the complete catastrophic failure of a key group member is already on full display, it can have the effect of cutting through all the small talk and making space for grace by setting the pace. Sin-confessing love-expressing mercy-manifesting truth-telling is the foundational norm. When communities are formed with our deepest brokenness already exposed and lying before us all - whether that is an AA meeting or small church 1820 - grace flows more easily.

I now have the long work ahead of me to rebuild trust where possible. And yet, merely insisting that I am trustworthy through swearing I'm telling the truth or making "cross my heart and hope to die" promises is a cheap and childish technique. No, broken trust can only be rebuilt as we let our yes be yes and our no be no over the long haul.

And note: as Jesus and the early Church repeatedly make clear, only those who get close enough to live in authentic community will get to see this process at work in all our lives. Those who want to pronounce judgements from a distance should be silent.

To quote this web site in another Sermon on the Mount study:

"Without journeying closely with a fallen sister or brother to observe and engage them with discernment, accountability, and compassion, we are merely armchair critics. Qualities like genuine repentance, humility, and submission to accountable input are hard to decipher from afar. This means all moral pontificating from far away can be laid to rest. Saints have better ways to invest their God-given energies. To be precise, when someone sins significantly, posting opinions online may feel good and public announcements may sound righteous, but they have very little to do with a New Covenant response to sin. Declarations at a distance are detached and, therefore, disqualified. They are performative, not reformative or restorative." (SM #17: Above & Beyond (Real Righteousness, Part 4)

Once again, simply loving and living the way of Jesus is the answer.

(Hashtag: #JesusIsGenius)


(Thoughts about meaning and application)

How should we apply this radical teaching of Jesus today? Although there are different opinions and theories, one thing we should all agree on - we should apply it!

For starters, let's not water down Jesus' teaching to be saying something like "It would be a good idea if we all don't lie so much." Jesus is calling his disciples to do something radical here, then and now - that is to refuse to participate in what was and is an accepted and even expected public ritual.

Today this might mean:

  • EXAMPLE #1... HIGH-LEVEL APPLICATION - IN BUSINESS: Some Anabaptist Christians do not sign contracts to affirm their intentions, hence the separatist and completely relational business practices of the Amish, Quakers, and Old Order Mennonites. They see contract-signing as a modern-day equivalent to oath-making. Not signing contracts places these communities completely out of step with any business practices of their surrounding society (including banking and insurance) and reinforces their isolation from surrounding culture. (Also note: Conservative Anabaptist wedding ceremonies do not include vow-making. The bride and groom simply affirm "I do" or "I will" when asked if they take the other as their spouse, to love, honour, and cherish, etc, for life. Plain and simple.)

  • EXAMPLE #2... MID-LEVEL APPLICATION - IN COURT: A few Christians do not swear to tell the truth (on a Bible or otherwise) in legal situations, but simply affirm the truth of their words. Anabaptist theologian Scot McKnight says "Let us be clear here: Jesus is talking about legal oaths and Jesus is against legal oaths" (Sermon on the Mount). Not swearing oaths also makes it difficult for a believer to hold either a civic or military position since we must swear an oath of loyalty to the nation and its laws in order to hold a position in government or military.

  • EXAMPLE #3... LOW-LEVEL APPLICATION - IN RELATIONSHIPS: Most Christians should be able to agree that we will not ask for nor offer promises ("Honest! I promise!") or swearing ("Really! I swear!") to increase trust in what we say to one another.

Most Christians today might say the first two examples above are too extreme (even though they are no more extreme than following this teaching would have been for disciples in Jesus' day). The Protestant Reformers, like Luther and Calvin, distinguished between public and private speech, saying that Jesus' teaching on oath-swearing only applies to private speech. In other words, oath-swearing for court, public office, and military membership is fine, but Christians shouldn't demand promises from one another in private conversations. That might sound like the most reasonable position to most of us, except for one problem - it's not what Jesus says. It takes some nuance to get to this position.

Regardless of how we interpret and apply this passage, we honour God by at least trying to interpret it and apply it correctly.

So here's a question:

If you are a follower of Jesus, when was the last time you thought about this teaching and actually adjusted your behaviour in light of it - in any way?

Jesus seems to be saying that valuing truth is so important, that his followers will refuse to participate in any culturally expected practices that water down this high value.

Think of it: if there are certain arenas of life where a vow, an oath, a promise, or a contract is necessary to affirm our high value of honesty, what does that say about the rest of our lives? Do we value truth any less in all other relational interactions? If I am not swearing an oath or declaring a promise. am I less expected to be fully honest at all times? Swearing oaths and making promises undercuts rather than elevates our overall esteem of honesty.

In a sense, promise-making and oath-taking are pure superstition. They are based on the naive belief that a person who otherwise cannot be trusted to speak the truth can be persuaded to speak truthfully through some sort of verbal formula or incantation. Oaths have no actual power.

Swearing oaths sure didn't help Peter tell the truth when he denied and disowned Jesus, swearing an oath that he did not know Jesus (Matthew 27:72, 74). Jesus calls his disciples away from this kind of fantasy and superstition.

Historically, oaths have been necessary for military service and the same reasoning used by theologians to dismiss this teaching of Jesus on oaths has been used to explain away his teachings on nonviolent peacemaking.

Martin Luther, after arguing that this anti-oath teaching of Jesus does not apply when we relate to the government (remember his private vs public speech idea) goes on to say:

"Similarly, when He forbids you to draw your sword, He does not mean that you should disobey the government if your territorial prince needs you or summons you to go to war." ~ Martin Luther (Exposition on the Sermon on the Mount)

So according to the great Reformers, and many Protestants today, Christians should be nonviolent... unless they need to be violent. That is, don't kill people privately, but if the government calls on you to kill publicly, be ready.

Sadly, this kind of reasoning has ruined much of the history of the Church. And yet, this kind of exegesis of the Sermon on the Mount comes up again and again in the formational documents of the Protestant Christian community, like The Heidelberg Catechism (1563) and The Westminster Confession of Faith (1647).

When we dismiss Jesus' teaching on oaths as irrelevant to our life and times, we have set the stage to do the same thing in what comes next in the Sermon on the Mount - his teachings on nonviolent peacemaking and radical enemy love.

The early Christ-followers seem to have taken Jesus' words here seriously and literally and refused to make vows, including the oath of military service. This continued as the dominant practice until the Constantinian Shift in the 4th century (see this study for more on the Constantinian Shift).

Jesus' little brother, leader of the Jerusalem church in the first century, seems to agree with Jesus (surprise!):

Above all, my brothers and sisters, do not swear—not by heaven or by earth or by anything else. All you need to say is a simple “Yes” or “No.” Otherwise you will be condemned. ~ James the brother of Jesus (James 5:12)

We can see how the early Church began as a new society with its own culture and values, making it out of step in significant ways with its surrounding power structures. Perhaps that is precisely Jesus' message here - be willing to be out of step with your surrounding culture on the little things, and you will be better prepared to go against the flow on the larger issues.

"Jesus' prohibition of oaths, for the first time explicitly in the Sermon on the Mount, places disciples in a tense relation with secular power. The state has never historically enjoyed being told 'no.'" ~ Frederick Dale Bruner (The Christbook)

And yet, we should be aware that the apostle Paul sometimes walks right up to the line of making promise-like assurances to be telling the truth (e.g., 2 Corinthians 1:23; Galatians 1:20; etc). And on at least one occasion Paul made a religious vow (Acts 18:18). What should we make of this Paul? Have you talked to James lately? (Christian scholars also debate whether or not Jesus answered under oath when questioned by the Sanhedrin in Matthew 26:63-64, but a close reading of the text shows how he avoided answering under oath.)

We know that Paul would bend his practices in order to connect relationally with different groups of people, religious and non-religious. Being clear on the gospel while also making concessions out of love for the sake of unity and/or evangelism was the way of the early Church. Paul took part in Jewish religious rituals (Acts 21:17-26) and the Jerusalem council asked gentile believers not to eat meat with blood in it for the sake of unity (Acts 15). Neither was morally necessary, but both were relationally loving.

Paul said his modus operandi was flexibility in practice for the sake of the gospel:

Though I am free and belong to no one, I have made myself a slave to everyone, to win as many as possible. To the Jews I became like a Jew, to win the Jews. To those under the law I became like one under the law (though I myself am not under the law), so as to win those under the law. To those not having the law I became like one not having the law (though I am not free from God’s law but am under Christ’s law), so as to win those not having the law. To the weak I became weak, to win the weak. I have become all things to all people so that by all possible means I might save some. I do all this for the sake of the gospel, that I may share in its blessings. ~ The apostle Paul (1 Corinthians 9:19-23)

So perhaps there are situations where, in order to be "very clear" to others outside the Jesus Movement, we might promise or give our signature or swear to be telling the truth. That amounts to basic other-centredness in communication. But if so, those situations are separate from how Kingdom citizens of the Jesus Nation relate to one another.

So what is the right application of all this for us today?

If we were to consider Jesus' Sermon on the Mount teaching in isolation, it would seem that the Amish, Mennonites, Quakers, and other traditional Anabaptists are the most accurate in their application (Example #1 above). However, the need for completely separate communities to live this out today ends up competing with other Jesusy values like close contact evangelism by being salt and light. It's a pickle.

So here are three recommendations:

  • RECOMMENDATION #1: Let's take this teaching seriously, which at the very least means asking how we are going to let it make a difference in how we live. And congratulations! If you're reading this study, and especially taking time to discuss it with others, you are already honouring Jesus by taking his teaching seriously. This too is an act of worship.

  • RECOMMENDATION #2: Let's be gracious with Christians who interpret Jesus' teaching differently. Whatever view you land on, remember that good and godly Christians believe differently.

  • RECOMMENDATION #3: Let's agree on the bare minimum of valuing honesty in all our interactions. Of course, to do this well, we will need to become communities of exceptional kindness, grace, and mercy since honesty alone will create friction that needs to be smoothed over with the oil of grace. Does your circle of fellowship exude grace, mercy, and love enough to invite total truth-telling?

Our more traditional Anabaptist and Quaker sisters and brothers have given us a name for this teaching: they call letting our yes be yes and our no be no, that is, saying what you mean and meaning what you say, "plain speech". They are skeptical of popular verbal embellishments (from oath-taking to promise-making, but also including flattery, titles, elaborations, exaggerations, and even an over-use of sarcasm) that seek to impress and sometimes deceive. We may have something to learn from their emphasis on plain speech.

"Christians are, thereby, committed to plain speech. We seek to say no more or no less than what needs to be said. Speech so disciplined is not easily attained. Too often we want to use the gift of speech as a weapon, often a very subtle weapon, to establish our superiority." ~ Stanley Hauerwas (Matthew)

Perhaps the best way forward is to continue to engage in secular contract-making to keep us economically and relationally engaged in our surrounding society (so we can be salt and light) while still standing out as taking Jesus seriously in specific oath-taking situations (like court). Or, at the very least, disciples of Jesus can all kick the cultural habit of highlighting our honesty by making or demanding promises in our many relational conversations, especially with fellow believers. Let our yes be yes and our no be no.

Whatever way forward we choose, taking this teaching seriously will take courage to overcome our cowardice. Are you ready?

Therefore each of you must put off falsehood and speak truthfully to your neighbor, for we are all members of one body. ~ The apostle Paul (Ephesians 4:25)


(One last thought)


Let us not forget that through this teaching, Jesus calls our religious desire to live by the letter of the law "evil" and invites us into a completely new Way of living, not by the letter, but by the Spirit. There is no going back to the way of law, even God's law, after the Gospel of grace has done its work. Jesus sets us free, from our sin and from our religion.

Jesus overrules (literally rules over, takes authority over) the old ways of the Old Covenant. Therefore Christ-followers do not just "follow the Bible" - we read the Bible so we can follow Jesus as we walk with the Spirit.

He has made us competent as ministers of a new covenant—not of the letter but of the Spirit; for the letter kills, but the Spirit gives life. ~ The apostle Paul (2 Corinthians 3:6)
Since we live by the Spirit, let us keep in step with the Spirit. ~ The apostle Paul (Galatians 5:25)
For those who are led by the Spirit of God are the children of God. ~ The apostle Paul (Romans 8:14)

Still sorting out what you think about this teaching of Jesus? We don't have to know all the answers and fathom all mysteries in order to take our first steps of faith. Simply read the Sermon on the Mount, begin to live what it says as best you understand it, and link arms with a few others on the same journey. Then you're keeping in step with the Spirit.

Freedom awaits. You're invited to join us.


(Scripture passages that relate to and deepen our understanding of this topic)

1 Corinthians 13:6; 2 Corinthians 3; Ephesians 4:15; 2 John 1:1-6


(Talk together, learn together, grow together)

  1. What is God revealing to you about himself through this passage?

  2. What is God showing you about yourself through this passage?

  3. What has been your experience of intimate, open, and honest friendship? Where do you find it? How does it benefit you? What will be your next step to foster more of it?

  4. What is one thing you can think, believe, or do differently in light of what you are learning?

  5. What questions are you still processing about this topic?


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