Matthew 5:33-37

As you know, we are in a section of our Lord’s teaching which exposes Pharisaical and Scribal distortions of God’s written Law-Word.  Last Lord’s Day we saw where Jesus discourages divorce, refutes the rabbinical misinterpretation of the Law, reaffirms the Law’s true meaning, censures the guilty party, defends the innocent, and through it all, upholds the sacredness and inviolability of the marriage bond as ordained by God.

As Dr. Greg Bahnsen said, there is an antithesis between human thought and truth of God.  And nowhere in Scripture is the antithesis more clearly exposed than it is here in the Sermon of the Mount.  Men – Pharisees – would that they could be justified by establishing their own standard and abiding by that ethic.  But out of their hearts come evil thoughts, murders, adultery and the like.  First of all, man must be justified, not by the evil manipulations of his own heart, but by the substitutionary atonement of the one perfect man – Jesus Christ.  Secondly, man cannot be set apart as holy by the devices of his own heart – but only by the Spirit of Christ.  And thirdly, man cannot live by his own law – but only by the Words spoken by God, the fullness of which is Christ Himself.

This morning we come to another example of the difference between the perverse hearts of men and God’s righteous Law-Word; and, as it was last Lord’s Day, so it is today – a passage of Scripture and a subject so little understood and so very seldom preached.  From the reaction to last Sunday’s preaching, I don’t think any of us had ever heard an entire sermon on the subject of divorce.  As critical an issue as it is in our society, it is never preached!

That, I am sure, will be the case today as well.  For what man in his right mind would preach a whole sermon on God’s Law concerning oaths and vows?  The whole congregation would be asleep in ten minutes!  And the next Sunday they would go some place where they could hear about the gifts of the Spirit, or examples from the preacher’s vacation.

But, as you will see before this half-hour is over, this is no minor issue!  This isn’t something we can just blow off and move on to something racier!  And it certainly isn’t something we can distort or pervert, as the Pharisees did, in order to avoid the guilt!

The Law of oaths has to do with the fundamental nature of God – His Truth and His faithfulness.  And it has to do with the basic relationship between God and His people.  And it has to do with the foundation of human relationships – the intent of the heart as it is expressed in language.  And it has everything to do with the honoring and glorifying of the Name of God!  For the Law of oaths and vows flows from, and is a direct application of, the third Commandment.

“You shall not take the Name of Yahveh your God in vain; for Yahveh will not leave unpunished him who takes His Name in vain.”


Now, what is the import of this command?  And what are the perversions of it that Jesus is condemning?

Most people incorrectly assume that the third Commandment merely prohibits cursing using the name of God.  And, indeed, it does prohibit cursing using the name of God.  But it prohibits much, much more!  To begin with, the phrase, “the name of Yahveh your God” does not refer only to the literal name of God.  It includes His literal name, and anything by which God makes Himself known, and, ultimately it refers to God Himself!

In our prayers we call upon Jesus as our substitute and as our advocate when we say, “In Jesus Name, Amen.”  That is a reference to Jesus – not just to His Name.  So, when the Scriptures refer to the “name” of God, the reference is comprehensively and ultimately to God Himself and all that He is.

Now, “in vain” means “as empty”, or, therefore, “falsely”, or, as a lie.  So, in its limited interpretation, the third Commandment primarily forbids calling upon God to confirm a falsehood.  But, as with all the Commandments, the greater includes the lesser – or the summary includes all its parts!

For example the sixth Commandment, as we saw a few weeks ago, does not merely prohibit murder – it also condemns hatred, malicious intent and revenge.  And, in the same way, the third Commandment not only prohibits calling upon God to witness to a falsehood, but it also forbids all lesser forms of irreverence for God!  And I say “lesser” with fear and trembling, for any irreverence for God brings guilt and uncleanness and poverty of spirit.

So the third Commandment requires that we, at all times, fear, honor and reverence God and His most holy Name – as well as His titles, attributes, ordinances and works – not limited to our speech, but especially in our speech and the ensuing consequences of our speech!  It especially forbids perjury and all profane, unnecessary oaths, all careless appeals to God, and all irreverent use of His Name.

And, Jesus, as He quotes from the Pharisaical tradition clearly understands that this is a third Commandment issue – and it is also clear that He sees the full extent of the distortions.  It is because the Pharisees had stopped using the name of God when they took oaths, or reached agreements or made promises.  And they did that because they held that a substitution for God’s name when they swore exempted them from the Biblical penalties for perjury!

So they swore by heaven, they swore by earth, they swore by the city of Jerusalem, they swore by the temple – and they even swore by their own heads!  God’s third Commandment had said that they would be held guilty if they swore falsely in His Name; so, in order to avoid the guilt, they stopped taking oaths in His Name!

See the distortion?  Rather than stop swearing falsely, which is the intent of the Command, they stopped using His Name so that they could continue swearing falsely!

And, as usual, when someone finds a good way to avoid the consequences of sin, the sin proliferates!  And where Scripture clearly prohibits unnecessary and frivolous oaths, the Pharisaical distortion of the Law freed them to swear often, and to treat those oaths and promises as non-binding.

But Jesus condemns both of those errors by showing that heaven, earth, Jerusalem, and even their own heads, have their ultimate reference point in God:  Heaven is the throne of God; the earth is His footstool; Jerusalem is the city of the Great King; and it is that King who controls even the hair on your heads!  In other words, when they swore by heaven, they swore by the God of Heaven because the universe and everything in it belongs to Him and is stamped with His glory.  And by swearing in those ways, the Pharisees failed to see that one still takes the name of God falsely no matter how he dresses up the language!

An oath is an oath before God and in His Name – whether His name is used or not!  Promises and agreements and contracts are made in the very presence of God – even if His Name isn’t used.  One can’t avoid the penalties of perjury and broken promises simply by substituting something else for the Name of God, or by leaving it off entirely!  The holiness, and the goodness, and the justice, and the sovereignty of Almighty God is offended when men undertake unnecessary and frivolous oaths – and when men swear falsely – and break promises – and enter agreements with mental reservations – and break contracts!

To break an oath is to trample on the holy Name of God – violating the third Commandment!  And, as with the other Divine Commandments, there is no shortage of genius when it comes to cunning excuses and self-serving rationalizations for breaking one’s oaths.

There was a great commander of armies in the middle ages who, having besieged a city, made promises that if the city surrendered, not one drop of blood would be shed.  And seeing their desperate situation, the people surrendered in order to save their lives.  And the commander fulfilled his promise not to shed a drop of blood – he buried them all alive!

I will come back to this point in a few minutes.  I only used that example to illustrate the language manipulations and mental reservations that are used by men to avoid the intent and content of an agreement!

The Jesuit sect of Roman Catholic priests developed the doctrine of mental reservations early in the middle ages.  And they said that if you had some mental reservations when you took an oath, then the oath could be deemed null and void if necessary.  Now, of course that has been an excuse for men since the beginning, but the Jesuits developed it and fine-tuned it theologically.  The rational, human mind has always been at least equal to, if not superior to, Scripture in Roman catholic thought.

But first, let us see exactly what Jesus says here in verse thirty-four.  Does He forbid all oaths?  Some say son.  “But I say to you to give not an oath at all; whether in the heavens, nor in the earth, nor by Jerusalem, nor should you promise with an oath upon your head.”  Is oath-taking forbidden here?

We must say no.  And for two very good reasons.  First, Jesus was condemning Pharisaical distortions to the Law of oaths, not condemning oath-taking itself.  We have already discussed the distortions, so we don’t have to say any more about them; just to mention that the perverted practice of substituting something else for God’s Name does not free a man to swear falsely.  Jesus says, “give not an oath at all” if that is going to be your practice!

The second reason why we must say that oath-taking is not forbidden is that all the rest of Scripture says that it is not!  God even commands that we swear in His Name.  And God never condemns what He simultaneously commands!  Listen to the Scriptures:


Deuteronomy six, thirteen; “You shall fear the Lord your God, and shall swear by His Name.”


Isaiah sixty-five, sixteen; “He who blesses himself in the earth, shall bless himself in the God of Truth; and he who swears in the earth, shall swear by the God of Truth....”


Jeremiah twelve, sixteen; “It shall come to pass, if they will diligently learn the ways of my people, to swear by My Name, Jahveh lives; (as they taught my people to swear by Baal), then shall they be built in the midst of My people.”


And God is even represented in Scripture as swearing – when He made His covenant with Abraham.  Listen to the writer of the letter to the Hebrews, chapter six:  “When God made promise to Abraham, because He could swear by no greater, He swore by Himself.”

And, our Lord Jesus, when He was put on oath by Caiaphus, the high priest, did not hesitate to answer.  Caiaphus said, “I adjure you (that is, I call upon you to swear) by the living God....”  And Jesus replied in the affirmative, in the accepted Rabbinical form.  “You said” (su eipan).

We won’t take the time to look at them now, but the apostles also used oath language many times to affirm the truth.  So it appears that oaths, themselves, are not forbidden in Scripture, but are freely used, in very specific circumstances; and even enjoined by God!

So, when Jesus says, here in our text, “give not an oath at all”, He means give not an oath at all – the way you are doing it!  Give not an oath at all, if you are going to do it falsely!  Give not an oath at all – if you are going to do it in the name of heaven, or earth, or Jerusalem, or on your own head!  Give not an oath at all – if you are going to forswear yourselves.  Give not an oath at all – instead of making a mockery of it!

Let your yes be “yes.”  And let your no be “no.”  Let it be “yes”, and then do yes!  Let it be “no”, and then do no!

It is clear from the Scriptures that calling upon the Name of God to witness to the truth is a solemn act of worship.  It is acknowledgement of His ultimate sovereignty in every given situation in history!  And, beyond that, every speech which flows from our mouths – where we make promises and agreements and speak the truth – He is sovereign witness to it all!  Anything beyond the affirmative “yes” – and then doing yes, or the negative “no” and doing no, is from evil, Jesus says.  What He means is that before the fall of man into sin, there was no such thing as an oath being required to witness to the truth!  Because man spoke only the truth!  But sin came in and man’s heart became evil!  So anything other than “yes”, or “no”, is out of that evil.  Jesus does not mean that an oath, in itself, is evil.  But only that the necessity for them comes out of the evil state of man!  The evil is in us – rather than in an oath.

So these entire five verses is a correction of the Pharisees’ perversions of God’s holy Law-Word.  They had refused to use the Name of God at all; and by not using it they had set themselves free to give an oath for anything – including frivolous and trivial matters.  They had loosed themselves from being bound by their oaths by using substitutes for the name of Yahveh.  They had protected themselves from the binding validity of their own oaths by mental reservations.  And, apparently, they had become adept at cagey, language manipulations in order to conceal their real intent in business agreements and contracts!  And God condemned them and laughed at them – because He was sovereign witness to it all.

Now, I don’t think there ought to be any questions in our minds about why Jesus places His correction of this perversion where He does.  It might seem strange to some that He would speak to a sixth Commandment issue, and then a seventh Commandment issue, and then go back to a third Commandment issue.  But it is no mystery to me.  The seventh Commandment has to do with adultery and divorce and the termination of an undisolvable contract.

And the Pharisees were experts at dissolving the marriage oaths and vows!  By the way, the strict definition of oath is calling upon God to witness a truth.  A vow is a promise made to God Himself.  So a marriage ceremony is both.  Two people give oaths to one another in the Name of Yahveh, and they make a vow to God not to separate that which He has joined together!

So, by putting their wives away for any trivial reason, the Pharisees were perjuring themselves before God, but covering it up with distortions of the Law and with mental reservations!  So Jesus puts it right here after adultery and divorce as an example of their perverted hearts as they manipulated the Mosaic Law to their own perjury.

Since Jesus was not condemning the use of oaths, and since all distorted uses of the Law with regard to oaths is condemned in this passage, let us finally take a quick look at some Biblical guidelines when obligating ourselves to oaths, vows or promises.

First, it almost goes without mentioning that one cannot bind himself to something which Scripture condemns or forbids.  In such a case, the focus of the guilt rests not only on breaking the obligation, but on making it in the first place!  One who obliges himself to sin is foolish, and is unclean before God, Whose Name has been taken in vain.

Secondly, we must speak the truth, and we must do what we say!  If we say “yes”, we must do all that we agree to do.  If we say “no” then we must refrain from doing what we negated.

Thirdly, if we appeal to God, then we must make sure that what we obligate ourselves to is absolutely necessary.  Superfluous swearing – trivial and frivolous use of obligatory language – and inane use of the Name of God – are forbidden by Jesus here in our text, as does His third Commandment.  We ought to purge from our vocabulary all trite sayings, such as “swear to God” or “honest to God” or “O my God” unless the occasion is so serious and solemn as to necessitate an oath.

Fourthly, when you take an oath – or obligate yourself, you must be prepared to abide by what you said, no matter what your circumstances and no matter what your personal interests are!  If you are not prepared to stand steadfastly by what you have promised, no matter what happens, then you should not make an oath!

Fifthly, when you give an oath, it must be in the Name of God!  You cannot leave Him out with the view of getting out of the obligation later should the circumstances change!  But if the situation is such that it necessitates a personal obligation, then it ought to be sealed in God’s Name.  There are a variety of ways God’s people have done that.  In the Scriptures we find these:  “Give glory to the God of Israel”; “as the Lord lives”’ “the Lord do so to me and more also”; “may the Lord be true and faithful witness”; “I adjure you by the living God”; “but I call God as witness to my soul”; “God is witness”; and “you are witnesses and so is God.”  In addition to these, Christianity has accepted some symbolic actions as well as words, which obligate us to fulfill our promises.  In court, for example, the raising of the right hand is a specific act of oath-taking to God that the truth will be spoken.  Placing a hand on the Bible, or kissing the Bible, has been used – both in acknowledging the Author of it as being a witness.  And Christians have taken a handshake between brothers who live in the body of Christ as a symbolic promise to fulfill an obligation.  The oath we take when we join the Church is an oath in God’s Name to support it and to seek its purity.  We also take an oath in God’s Name to help raise each other’s children at their baptisms.  And the list goes on.

Lastly, the language of an oath must be unequivocal and unambiguous, so as to be clearly understood by all the parties.  Remember, Jesus said that His people are pure in heart.  Purity of heart requires no mental reservations, and no language manipulations.  Nothing hidden on the folded side; everything clear and perspicuous.  That is why I am always after you to put everything in writing when you make agreements.  That way your obligations to one another are clearly spelled out – and God’s Name isn’t called as a witness to a falsehood.

For there is no falsehood in Him.  And our faithfulness to what we say is to mirror His faithfulness.

Law of oaths has to do with something so fundamental as the faithfulness to trustworthiness of God Himself – as mirrored.  God be witness to the truth!