Albert Barnes Commentary 1 John 2:29

"If ye know that he is righteous, ye know that every one also that doeth righteousness is begotten of him." — 1 John 2:29 (ASV)

If ye know that he is righteous. This is not said as if there could be any doubt on the subject, but merely to call their attention to it as a well-known truth, and to state what followed from it. Everyone who has any true acquaintance with God, must have the fullest conviction that he is a righteous Being. But, if this is so, John says, then it must follow that only those who are truly righteous can regard themselves as begotten of him.

Ye know. The marginal reading is know ye. The Greek will bear either construction, and either would make good sense. Assuming that God is righteous, it would be proper to state, as in the text, that it followed from this that they must know that only those who are righteous can be regarded as begotten of him; or, assuming this to be true, it was proper to exhort them to be righteous, as in the margin. Whichever interpretation is adopted, the great truth is taught, that only those who are truly righteous can regard themselves as the children of God.

That every one that doeth righteousness is born of him. Or rather, is begotten of him; is truly a child of God. This truth is everywhere taught in the Bible and is worthy of being often repeated. No one who is not, in the proper sense of the term, a righteous man, can have any well-founded pretensions to being regarded as a child of God. If this is so, then it is not difficult to determine whether we are the children of God.

1. If we are unjust, false, dishonest, we cannot be his children.
2. If we are indulging in any known sin, we cannot be.
3. If we are not truly righteous, all visions and raptures, all zeal and ardour, though in the cause of religion, all that we may pride ourselves on in being fervent in prayer, or eloquent in preaching, is vain.
4. If we are righteous, in the true and proper sense, doing that which is right toward God and toward men, to ourselves, to our families, to our neighbours, to the world at large, to the Saviour who died for us, then we are true Christians; and then, no matter how soon he may appear, or how solemn and overwhelming the scenes that shall close the world, we shall not be ashamed or confounded, for we shall hail him as our Saviour, and rejoice that the time has come that we may go and dwell with him forever.