For if our heart condemn us He proves, on the other hand, that they in vain possess the name and appearance of Christians, who have not the testimony of a good conscience. For if any one is conscious of guilt, and is condemned by his own heart, much less can he escape the judgment of God. It hence follows, that faith is subverted by the disquiet of an evil conscience. He says, that God is greater than our heart, with reference to judgment, that is, because he sees much more keenly than we do, and searches more minutely and judges more severely. For this reason, Paul says, that though he was not conscious of wrong himself, yet he was not therefore justified, (1-Corinthians 4:4;) for he knew that however carefully attentive he was to his office, he erred in many things, and through inadvertence was ignorant of mistakes which God perceived. What then the Apostle means is, that he who is harassed and condemned by his own conscience, cannot escape the judgment of God. To the same purpose is what immediately follows, that God knoweth or seeth all things For how can those things be hid from him which we, who in comparison with him are dull and blind, are constrained to see? Then take this explanation, "Since God sees all things, he is far superior to our hearts." For to render a copulative as a causal particle is no new thing. The meaning is now clear, that since the knowledge of God penetrates deeper than the perceptions of our conscience, no one can stand before him except the integrity of his conscience sustains him. But here a question may be raised. It is certain that the reprobate are sometimes sunk by Satan into such stupor, that they are no longer conscious of their own evils, and. without alarm or fear, as Paul says, rush headlong into perdition; it is also certain, that hypocrites usually flatter themselves, and proudly disregard the judgment of God, for, being inebriated by a false conceit as to their own righteousness, they feel no convictions of sin. The answer to these things is not difficult; hypocrites are deceived because they shun the light; and the reprobate feel nothing, because they have departed from God; and, indeed there is no security for an evil conscience but in hiding-places. But the Apostle speaks here of consciences which God draws forth to the light, forces to his tribunal, and fills with an apprehension of his judgment. Yet; it is at the same time generally true, that we cannot have a calm peace except that which God's Spirit gives to purified hearts; for those who, as we have said, are stupefied, often feel secret compunctions, and torment themselves in their lethargy.

For if our heart condemn us - We cannot hope for peace from any expectation that our own hearts will never accuse us, or that we ourselves can approve of all that we have done. The reference here is not so much to our past lives, as to our present conduct and deportment. The object is to induce Christians so to live that their hearts will not condemn them for any secret sins, while the outward deportment may be unsullied. The general sentiment is, that if they should so live that their own hearts would condemn them for present insincerity and hypocrisy, they could have no hope of peace, for God knows all that is in the heart. In view of the past - when the heart accuses us of what we have done - we may find peace by such evidences of piety as shall allay the troubles of an agitated soul, 1-John 3:9, but we cannot have such peace if our hearts condemn us for the indulgence of secret sins, now that we profess to be Christians. If our hearts condemn us for present insincerity, and for secret sins, we can never "persuade" or soothe them by any external act of piety. In view of the consciousness of past guilt, we may find peace; we can find none if there is a present purpose to indulge in sin.
God is greater than our heart, and knoweth all things - We cannot hope to find peace by hiding anything from his view, or by any supposition that he is not acquainted with the sins for which our consciences trouble us. He knows all the sins of which we are conscious, and sees all their guilt and aggravation as clearly as we do. He knows more than this. He knows all the sins which we have forgotten; all those acts which we endeavor to persuade ourselves are not sinful, but which are evil in his sight; and all those aggravations attending our sins which it is impossible for us fully and distinctly to conceive. He is more disposed to condemn sin than we are; he looks on it with less allowance than we do. We cannot hope, then, for a calm mind in any supposition that God does not see our sins as clearly as we do, or in any hope that he will look on them with more favor and indulgence. Peace cannot be found in the indulgence of sin in the hope that God will not perceive or regard it, for we can sooner deceive ourselves than we can him; and while therefore, 1-John 3:19, in reference to the past, we can only "persuade" our hearts, or soothe their agitated feelings by evidence that we are of the truth now, and that our sins are forgiven; in reference to the present and the future, the heart can be kept calm only by such a course of life that our own hearts and our God shall approve the manner in which we live.

If our heart condemn us - If we be conscious that our love is feigned, we shall feel inwardly condemned in professing to have what we have not. And if our heart condemn us, God is greater than our heart, for he knows every hypocritical winding and turning of the soul, he searches the heart, and tries the reins, and sees all the deceitfulness and desperate wickedness of the heart which we cannot see, and, if we could see them, could not comprehend them; and as he is the just Judge, he will condemn us more strictly and extensively than we can be by our own conscience.

For (4) if our heart condemn us, God is greater than our heart, and knoweth all things.
(r) If an evil conscience convicts us, much more ought the judgment of God condemn us, who knows our hearts better than we ourselves do.

For if our heart condemn us,.... Of want of love to the brethren, and of hypocrisy in it, as well as of any other sin; for the conscience, which is meant by the heart here, is accuser, witness and judge; it accuses of the evil of sin, and is as good as a thousand witnesses; and upon its own testimony pronounces guilty, and condemns.
God is greater than our heart: for he is the Maker of it, and he has the power over it, and the management of it; it is in his hands, and to be turned by him as he pleases; and he is the searcher and trier of it; and besides, is a swifter witness than conscience, and a superior Judge unto it.
And knoweth all things; that are in the heart; the principles of actions, and all the actions of men, for which their hearts condemn them; and all the sinfulness in them, and the aggravations of them; wherefore, as he knows them more perfectly, he judges of them more exactly, and will reprove more sharply, and condemn more severely for them: hence, if the condemnation of men's hearts and consciences be so very great, as sometimes to be intolerable and insupportable, what will be the righteous judgment, and dreadful condemnation of God? how fearful a thing will it be to fall into the hands of the living God! this sense is confirmed by the Syriac version rendering it, "how much greater is God than our hearts?" there is another sense given by some, which is not by way of terror, but comfort, and that is, that if the hearts of believers accuse, reprove, and condemn for sin through unbelief, or want of clear view of pardon and righteousness by Christ, God is greater, as in power, so in knowledge, than the hearts of men; and he knows the thoughts he has towards them, which are of peace, and not of evil; the covenant he has made with his Son, of which he is ever mindful; and what his Son has done, that he has made full satisfaction for sin, and brought in an everlasting righteousness: so that let sin, or Satan, or the world, or the law, or their own hearts condemn them, there is no condemnation of any avail unto them. But the former sense seems best to agree with the context.

LUTHER and BENGEL take this verse as consoling the believer whom his heart condemns; and who, therefore, like Peter, appeals from conscience to Him who is greater than conscience. "Lord, Thou knowest all things: thou knowest that I love Thee." Peter's conscience, though condemning him of his sin in denying the Lord, assured him of his love; but fearing the possibility, owing to his past fall, of deceiving himself, he appeals to the all-knowing God: so Paul, 1-Corinthians 4:3-4. So if we be believers, even if our heart condemns us of sin in general, yet having the one sign of sonship, love, we may still assure our hearts (some oldest manuscripts read heart, 1-John 3:19, as well as 1-John 3:20), as knowing that God is greater than our heart, and knoweth all things. But thus the same Greek is translated "because" in the beginning, and "(we know) that" in the middle of the verse, and if the verse were consolatory, it probably would have been, "Because EVEN if our heart condemn us," &c. Therefore translate, "Because (rendering the reason why it has been stated in 1-John 3:19 to be so important to 'assure our hearts before Him') if our heart condemn (Greek, 'know [aught] against us'; answering by contrast to 'we shall know that we are of the truth') us (it is) because God is greater than our heart and knoweth all things." If our heart judges us unfavorably, we may be sure that He, knowing more than our heart knows, judges us more unfavorably still [ALFORD]. A similar ellipsis ("it is") occurs in 1-Corinthians 14:27; 2-Corinthians 1:6; 2-Corinthians 8:23. The condemning testimony of our conscience is not alone, but is the echo of the voice of Him who is greater and knoweth all things. Our hypocrisy in loving by word and tongue, not in deed and truth, does not escape even our conscience, though weak and knowing but little, how much less God who knows all things! Still the consolatory view may be the right one. For the Greek for "we shall assure our hearts" (see on 1-John 3:19), is gain over, persuade so as to be stilled, implying that there was a previous state of self-condemnation by the heart (1-John 3:20), which, however, is got over by the consolatory thought, "God is greater than my heart" which condemns me, and "knows all things" (Greek "ginoskei," "knows," not "kataginoskei," "condemns"), and therefore knows my love and desire to serve Him, and knows my frame so as to pity my weakness of faith. This gaining over the heart to peace is not so advanced a stage as the having CONFIDENCE towards God which flows from a heart condemning us not. The first "because" thus applies to the two alternate cases, 1-John 3:20-21 (giving the ground of saying, that having love we shall gain over, or assure our minds before Him, 1-John 3:19); the second "because" applies to the first alternate alone, namely, "if our heart condemn us." When he reaches the second alternate, 1-John 3:21, he states it independently of the former "because" which had connected it with 1-John 3:19, inasmuch as CONFIDENCE toward God is a farther stage than persuading our hearts, though always preceded by it.

For if we have not this testimony, if in anything our heart, our own conscience, condemn us, much more does God, who is greater than our heart - An infinitely holier and a more impartial Judge. And knoweth all things - So that there is no hope of hiding it from him.