1 John 3:4-6

Verse 4

Sin is the transgression of the law - The spirit of the law as well as of the Gospel is, that "we should love God with all our powers, and our neighbor as ourselves." All disobedience is contrary to love; therefore sin is the transgression of the law, whether the act refers immediately to God or to our neighbor.
Verse 5

And ye know that he was manifested to take away our sins - He came into the world to destroy the power, pardon the guilt, and cleanse from the pollution of sin. This was the very design of his manifestation in the flesh. He was born, suffered, and died for this very purpose; and can it be supposed that he either cannot or will not accomplish the object of his own coming?

In him is no sin - And therefore he is properly qualified to be the atoning sacrifice for the sins of men.
Verse 6

Whosoever abideth in him - By faith, love, and obedience.

Sinneth not - Because his heart is purified by faith, and he is a worker together with God, and consequently does not receive the grace of God in vain. See on 1Jn 3:3 (note).

Hath not seen him - It is no unusual thing with this apostle, both in his gospel and in his epistles, to put occasionally the past for the present, and the present for the past tense. It is very likely that here he puts, after the manner of the Hebrew, the preterite for the present: He who sins against God doth not see him, neither doth he know him - the eye of his faith is darkened, so that he cannot see him as he formerly did; and he has no longer the experimental knowledge of God as his Father and portion.
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