And hereby we shall know that we are of the truth, and shall persuade our hearts before him --
The verse follows the call to love not in word or talk but in deed and in truth. Two phrases carry the weight: being "of the truth," and having a heart set at rest "before Him."
The phrase is not asking whether a person is a Christian.
Knowing "that we are of the truth" does not mean knowing that we are Christians. Some have taken it that way. But the apostle wrote to these people because they were already Christians, because they knew the Father, because their sins were forgiven them for His name's sake. He urges them to love not "in word or talk, but in deed and in truth," and then adds, "By this we shall know that we are of the truth." That is, we are truly walking in the truth; the truth has hold of us, we are "of the truth."
One writer compares this assurance to buying a fruit tree.
A man buys a tree sold to him as one kind of apple tree. To reassure him, the grower who raised it gives him a signed certificate. That is good, but a mistake is possible. Then the season comes, and he picks that exact kind of apple from the tree. Now his assurance is as complete as assurance can be. When the love and the truth of God bear their fruit in the life and in deed, our hearts may well be assured.
Some have used this verse to argue that certainty of acceptance with God rests on our works.
It is useless to appeal to 1 John 2:3 and 1 John 3:18-19 to prove that Scripture makes the full assurance of our acceptance depend on our works or our experiences. The apostle deals with a completely different question. In this very letter he assumes that our acceptance is already settled, even for the youngest children in God's family… So in chapter 3 the question is "assurance of heart." It is not about finding out whether we have a part in Christ. It is about keeping our confidence toward God unbroken.
Another writer names what is at stake.
"Reassure our heart before Him." The subject here is clearly freedom with God, not salvation or condemnation.
The same writer weighs the word behind "reassure," which older translations render "assure."
To be "of the truth" is the basis of truthfulness in practice… If we are kept watchful and earnest before God, loving and humble as well, "we shall know that we are of the truth." This inspires boldness or confidence before God. The word is not exactly "assure," but "persuade our hearts before Him." That is the simple and literal meaning. What is meant is not standing, nor assurance of faith, but the heart's boldness before God in a walk of sincere and active love.
The next verse takes the opposite case: a heart that condemns. Commentators differ on why God is greater than our heart. One takes it as a call to self-judgment, not comfort.
Why should we want comfort when we have displeased Him? He wants us to be humbled instead… "For if our heart condemns us" — this is just what our heart does when we walk badly. Something grieves the Spirit of God, and we have not judged ourselves before Him as we should.
Another takes the same words as pointing a troubled believer to God.
What is the resource of the soul in such a case? "God is greater than our heart, and knows everything." To turn away from God would be complete folly, for in such a need He is our only Refuge. Moreover, He knows more than we do about our failure, and knows also how to overcome it.
This assurance also decides how we fare in prayer.
If this kindness to one another is missing, our hearts will condemn us, and God knows this. But if we are walking in true love for one another, we have confidence toward God, and we receive answers to prayer… Nothing could be clearer. If we want to succeed in prayer, we must be obedient children, and walk in real, practical love with our brothers and sisters in the Lord.
One writer pictures this with an unpaid debt.
It is not a question of being, or not being, children of God. It is a question of the children being on happy, confident terms with their Father. If I owe a man a debt I should have paid, meeting him is awkward. But if there is nothing between us, and I trust his generosity, I can go to him confidently with a request.
- Cause — Love shown in deed, not in talk, is what "by this" points back to. The assurance of this verse has no other source.
- Proof — Being "of the truth" means walking in it now, not discovering for the first time that you belong to God.
- Place — The assurance is before Him. It is a heart made bold in God's presence, not a verdict on your salvation.
- Warning — When the heart does condemn, God knows more than we do. Commentators differ: does that humble us, or shelter us?
- Result — A heart that does not condemn us gives confidence toward God, and there answered prayer begins.
that if our heart condemn us, God is greater than our heart and knows all things.
Sometimes our own heart accuses us, and John meets that moment with one fact: God is greater than our heart. Does that greatness quiet the accusation, or sharpen it?
In this verse "heart" means conscience, not affection. The same word does different work in different places:
In Hebrew the word covers everything: conscience, soul, spirit, and heart. So heart is really a figure of speech, since otherwise it is a piece of my flesh connected with the circulation of the blood. Take "if our heart does not condemn us" — there it is in the sense of conscience. "Love God with all your heart" — there it is the affections.
The accusation follows love that is claimed but never shown:
The heart itself secretly protests against such unreality, and condemns the selfishness it has shown. The contrast to the love of Christ is felt, and the conscience will be heard. Confidence in God's help in its own hour of need is shaken, and prayer is hindered. How can hands be lifted up to God in prayer that have been closed to a brother's needs?
God's greatness here is a matter of knowledge. He often sees what we cannot even name:
"God is greater than our heart." He knows us better than we know ourselves. As soon as our heart allows something that cannot stand before God, our communion and liberty with Him suffer. Now sometimes we do not know where to find what has unsettled our fellowship with God. What has done it? After a little searching we will discover that our hearts are tolerating some elements of evil which God sees and will not allow.
Commentators differ on why this is said. One reading takes it as a check on comforting ourselves while our ways are wrong:
I think the words about God being greater than our heart and knowing all things come in not to comfort us when our heart condemns us, but to deepen self-judgment. What is in question is our present state, not our standing before God.
Another reading turns the troubled believer toward God as his only refuge:
What is the resource of the soul in such a case? "God is greater than our heart, and knows all things." To turn away from God would be utter folly, for in such a need He is our only refuge. What is more, He knows more than we do about our failure, and He knows how to overcome it. This must of course humble our hearts, as we admit that God is greater; but with the humbling will come blessing. So at every failure and self-condemnation, let us turn fully to God, whose wisdom and love we can trust. There is restoration here, and grace to lead us rightly in the future.
One writer finds both sides in a real man:
Peter had boasted confidently of his love for the Lord, but he had failed to show it in deed. He had denied Him three times with oaths and curses. So the Lord questioned him three times on the point, letting a probe down into his conscience. Instead of feeling assured, Peter's heart condemned him, though he knew that deep down he did love the Lord. If Peter had some sense of his failure, the Lord who knew all things saw the depth of it as Peter did not. And yet by that very fact He also knew that, despite the failure, genuine love was there. So Peter said, "Lord, You know everything; You know that I love You." He was glad to throw himself on the fact that "God is greater than our hearts, and knows all things." So may we be, when we are in a similar situation.
An accusing heart is not meant to last. The answer is honest confession:
God must have evil judged in all who draw near to Him. It is the same with prayer as with worship: there can be neither where there is defilement. But how good it is that God has provided for every need of His people in a defiling scene. And so God has appointed that "If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness." When the way of release is this simple, why should anyone walk with a burdened conscience?
- Heart. Here the word means conscience, not affection. It is the inward voice that speaks up when we claim love but do not show it.
- Condemns. Love withheld in deed sets it off. Hands closed to a brother's need cannot be lifted up in prayer.
- Greater. God knows us better than we know ourselves. He sees the evil our hearts allow, even when we cannot trace what has spoiled our fellowship with Him.
- Knows. Commentators differ on the aim of that greatness. Some say it deepens self-judgment about our present state, not our standing. Others say it points us to our only refuge, since God knows how to overcome the failure He sees.
- Confesses. Peter is the pattern. He threw himself on the Lord who knew everything. Confession is the way back from a burdened conscience to confidence.