What did Jesus mean that "by your words you will be justified" (Matthew 12:37)?

Hence the Lord pronounces them a generation of vipers. "The tree is known by his fruit." It was a bad tree, and no good fruit would He expect from it. "O generation of vipers," He adds, "how can ye, being evil, speak good things? For out of the abundance of the heart the mouth speaketh. A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things. But I say unto you, That every idle word (that is, I suppose, everything betraying contempt for God) that men shall speak, they shall give account thereof in the day of judgment. For by thy words thou shalt be justified, and by thy words thou shalt be condemned" (vers. 34-37). What God insists upon is testimony to Jesus. These idle words betray the heart's rejection of Jesus, and slight the Holy Ghost's testimony to Him. "By thy words thou shalt be justified, and by thy words thou shalt be condemned." It is with the mouth that confession is made unto salvation; and the words that leave out Jesus prove that the heart prefers its sin to Him. The words of the mouth evidence the state of the heart. They are the outward expression of the feelings, and they show a man in one way as much as his conduct does in another. If the heart is evil, the words are evil, the conduct is evil: all therefore comes into judgment.

The leaven of the Pharisees is still at work. This leaven has leavened, indeed, the whole lump. Ritualistic, religious, moral Christendom, professing, and not possessing, is the direct descendant of the Pharisee of old and as such the offspring of vipers as much as they were. How little the radical, complete corruption of man is believed in Christendom, how little it is taught. Man with the good spark in him (as they claim), developing it by religiousness and the use of his own will, becomes and is his own Saviour. The Lord is looked upon not as Lord, but as Jesus of Nazareth, whose life is an example, while the atonement, the blood, is set aside and rejected. The wicked heart cannot bring forth good things. Fine and polished, sweet and harmonious, may be the language of the cultured, religious, unsaved man, but proceeding from an evil heart it can never please God. "For out of the abundance of the heart the mouth speaks. The good man out of the good treasure brings forth good things and the wicked man out of the wicked treasure brings forth wicked things. But I say unto you that every idle word which men shall say, they shall render an account of it in judgment day; for by thy words thou shalt be justified, and by thy words thou shalt be condemned" (verses 35-37).

These words have been misunderstood and much misapplied and all this by wresting these words out of their connection. They are mostly applied in connection with that unscriptural phrase and doctrine, "universal judgment." According to this, even the words will be weighed and judged, and only then in that hour of judgment, will it be known, according to this teaching, who will be saved and who is lost. Our Lord did not teach this here nor is it taught anywhere else. These Pharisees were proud of their works and were self-righteous. If they relied on their works as a means of their justification and salvation they have to expect a judgment accordingly; every idle word is to be judged, which means utter, absolute condemnation. Their words could not be good because they were wicked. May the self-righteous, religious man remember this. Absolute condemnation awaits him. Salvation is by grace, and by that salvation man receives a good treasure and brings forth good things. Out of the abundance of the heart the mouth then speaks. Furthermore, the word "idle" means useless, barren. All that which man speaks out of himself is barren and useless. The believer, however, living after the Spirit, will not utter useless words, but that which is in honor of the Son of God. As believers, we should bear constantly in mind that we must all appear before the judgment seat of Christ, not for a decision of eternal salvation, this was settled when the believer trusted in Christ, but for rewards. Surely then our deeds, our works and our words will be either approved or disapproved.

"By thy words thou shalt be justified and by thy words thou shalt be condemned." This has also a reference to the familiar passage in Romans 10: "If thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised Him from the dead, thou shalt be saved." And wherever there is not this confession springing from the belief of the heart there is condemnation.

(4) That generation had proved its condition; the tree was known by its fruit. It was a viper's brood, from which no good thing could be expected any longer. Their mouth was speaking now out of the fulness of the heart. The treasures of the good man were good things, but the treasures of the evil, evil. Thus an idle word might prove a man's condition, and in the day of judgment all such would be taken into account, ― by his words a man be justified or condemned. How impossible, then, for any to escape, who has not found his shelter in Him whom Israel here refuses!

But that is not the end of the matter. Every idle word that men speak they will be called upon to account for in the day of judgment. This is true even of idle (that is, worthless or unfruitful) words. How much more so when the words are positively wicked! For by one's words (good words) he would be justified. and by his words (idle words) he would be judged. The world's government does not act an this principle: freedom of speech allows a shameful excess of evil words. Sometimes people are sued for libel of others; but the most repulsive language against God is considered of no consequence. God's judgment will specially expose all this, as Jude 15 & 16 bears strong witness, with swift, unsparing vengeance against men's hard words, no less than against their evil actions.

The sad fact was that these Pharisees were utterly corrupt trees, a generation of vipers, and their evil words had been just the expression of the evil of their hearts. In verses 33-37, the Lord unmasked their hearts in this way, and declared they would be judged by their words. If men will have to render account of even idle words in the day of judgment, what will evil words such as these merit? In that day by their words they would be utterly condemned.

But there is another way in which we may glorify God, or do Him great dishonour; not by our activity but by our speech. For out of the abundance of the heart the mouth speaks. As our Lord added, "The good man out of the good treasure of the heart bringeth forth good things; and the wicked man out of the wicked treasure bringeth forth wicked things. But I say unto you, that every idle word which men shall say, they shall render an account of it in judgment-day; for by thy words thou shalt be justified, and by thy words shalt thou be condemned" (Matt. 12:35-37). On scarce anything are men, and even Christians, more distant practically from the mind of God than on the use and in the licence claimed for the tongue. On the other hand who does not know the dead and gloomy and resentful silence when the name of the Lord Jesus is brought into any general company? It matters not how reverent be the spirit in which it is uttered, or how apt the application, or how necessary and conclusive for the truth's sake: man cannot forgive it. The name is inopportune save from a pulpit; it is an offence to the world, high or low, which cast Him out and crucified Him. Notwithstanding the desperate effort to make out that all is changed for so many ages, and that the adornment of the tomb, the picture, or the sculptor, proves the heart's homage in our day, the implacable enmity underneath does not fail to betray itself; and God is not deceived by a vain show. With the heart it is believed unto righteousness, and with mouth confession is made unto salvation. God will have His Son honoured as Himself where He was rejected; and those who honour Him by hearing His words and believing Him Who sent Him have life eternal; while those who disbelieve Him must perish, their ways being as bad as their words to His dishonour.

It is one of those striking facts which one overlooks, but which have their importance in the character and teaching of Scripture, that we have not even the word "justified" in the teaching of any of the Apostles but Paul, save the well-known corrective statements in James. Nor is "righteousness" used by them in what is called the forensic, i.e., judicial sense. We have Paul stating it too in Acts 13. In the gospel, we have "Wisdom justified of her children," "This man went down justified rather than the other" (Luke), "By thy words thou shalt be justified" (Matthew), "He willing to justify himself" (Luke), "Ye are they which justify yourselves," and "The publicans justified God." These are all in the Gospels, otherwise it is as I have said. So we have seen of the Church - Christ naming it as His building - the Acts historically as a fact in the world, and manifest - else only in Paul.

"Every idle word that men shall speak." An idle word is what has God in contempt. It is a lesson to show the solemnity of the right use of the tongue. It is an unruly member, but God can keep it in check. There is a proverb that says, "He that loves pureness of heart, for the grace of his lips the king shall be his friend." The heart and lips go together. While we are speaking of that, I should like to say that as far as words are concerned, if we say anything wrong we should judge it. But before the word is the intention, and it is better to judge intentions than words; before the intention is the thought, and it is better still to judge the thought in the light of the word of God which is living and powerful, and a discerner of the thoughts and intents of the heart.

Thus is the commandment made exceeding broad and deep. The axe is laid to the root of the evil tree. All violent feelings are judged as in God's sight, and every evil word of malice and contempt shown to be of sinful and dangerous consequence. As He said later in the same Gospel (Matt. 12:37), "By thy words thou shalt be justified, and by thy words thou shalt be condemned." Here He warns, not so much of every light word, but of wrath, hatred, and contempt. The Judge of all the earth, Himself despised by man and abhorred by the nation, as was soon proved, could not fail to discern aright.

Whether active or whether lying down, we are always subject to God's comprehension (v. 3), and our activities are always under His observation. Every word that issues from our lips is perfectly known by Him who has said, "By your words you will be justified, and by your words you will be condemned" (Matt. 12:37). For our words are an index to the condition of our hearts, and the great Judge of all takes full account of these as well as our actions. If we keep this in mind, we shall surely be preserved from much evil.