1 John 3:20

This means: through truth (and truth will be in us when our words correspond to our deeds) we shall reassure our conscience. For by the word "heart" he means conscience. How then shall we reassure it? By placing ourselves in such a position as to …

For if our heart reproves us, etc. If our conscience itself accuses us within, because we are not doing our good works with the right intention, how can we hide our knowledge from Him to whom it is sung: Behold, Lord, you have known all …

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.

Conscience is God's vicegerent, calls the court in his name, and acts for him. The answer of a good conscience towards God, 1 Pet. iii. God is chief Judge of the court: If our heart condemn us God is greater than our heart, superior to our heart and conscience in power and judgment; hence the act and judgment of the court are the act and judgment of God; as, 1.

God is a greater witness than our conscience, and knoweth more against us than it does: he knoweth all things; he is a greater Judge than conscience; for, as he is supreme, so his judgment shall stand, and shall be fully and finally executed.

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.

[Another Sermon by Mr. Spurgeon, on verse 21, is #1855, Volume 31—WHAT IS THE VERDICT?.] THE fault of a very large number of persons is that they will not lay spiritual things to heart at all, but treat them in a very superficial manner—or, if they exercise any judgment concerning them, it is of the most superficial kind. Now this is very foolish because, to say the least, the soul is of some value.

[Another Sermon by Mr. Spurgeon, on verse 21, is #1855, Volume 31—WHAT IS THE VERDICT?.] THE fault of a very large number of persons is that they will not lay spiritual things to heart at all, but treat them in a very superficial manner—or, if they exercise any judgment concerning them, it is of the most superficial kind. Now this is very foolish because, to say the least, the soul is of some value. And if men lay to heart the loss of their bodily health or of their estate, much more ought they to lay to heart anything which concerns their soul. It is very wicked as well as very foolish because, in refusing to lay spiritual matters to heart, we virtually tell the God who made us that He is of no account to us, that we are quite indifferent to His Being, to His Character, or to His commands. It is telling Him that we do not desire to be obedient to Him and that if we have been disobedient to Him, we do not trouble ourselves about that. It is also as dangerous as it is foolish and wicked to be unconcerned about spiritual matters, for God will not be trifled with and, one of these days, those who would not lay eternal things to heart will find their souls full of anguish—and with remorse they will be visited for this lightness of theirs. Whereas, today, like those of old who were invited to the wedding of the king's son, they make light of it and go their way to their farm or to their merchandise, there will come a day when they would give all their farms and their merchandise if they might have but another hour's respite, another invitation of mercy and another opportunity to seek and find the Savior.

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.

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, 1Jn 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. […]