Conduct will show who is a man’s spiritual father

^4-6 Everyone who commits sin breaks God’s law, for that is what sin is, by definition—a breaking of God’s law. You know, moreover, that Christ became man for the purpose of removing sin, and he himself was quite free from sin. The man who lives “in Christ” does not habitually sin. The regular sinner has never seen or known him.

^7-9 You, my children, are younger than I am, and I don’t want you to be taken in by any clever talk just here. The man who lives a consistently good life is a good man, as surely as God is good. But the man whose life is habitually sinful is spiritually a son of the devil, for the devil is behind all sin, as he always has been. Now the Son of God came to earth with the express purpose of liquidating the devil’s activities. The man who is really God’s son does not practise sin, for God’s nature is in him, for good, and such a heredity is incapable of sin.