John 3:17-21

Verse 17

For God sent not, etc. - It was the opinion of the Jews that the Gentiles, whom they often term the world, עלמה olmah, and אומות העולם omoth haolam, nations of the world, were to be destroyed in the days of the Messiah. Christ corrects this false opinion; and teaches here a contrary doctrine. God, by giving his Son, and publishing his design in giving him, shows that he purposes the salvation, not the destruction, of the world - the Gentile people: nevertheless, those who will not receive the salvation he had provided for them, whether Jews or Gentiles, must necessarily perish; for this plain reason, There is but one remedy, and they refuse to apply it.
Verse 18

He that believeth - As stated before on Joh 3:16.

Is not condemned - For past sin, that being forgiven on his believing in Christ.

But he that believeth not - When the Gospel is preached to him, and the way of salvation made plain.

Is condemned already - Continues under the condemnation which Divine justice has passed upon all sinners; and has this superadded, He hath not believed on the name of the only begotten Son of God, and therefore is guilty of the grossest insult to the Divine majesty, in neglecting, slighting, and despising the salvation which the infinite mercy of God had provided for him.
Verse 19

This is the condemnation - That is, this is the reason why any shall be found finally to perish, not that they came into the world with a perverted and corrupt nature, which is true; nor that they lived many years in the practice of sin, which is also true; but because they refused to receive the salvation which God sent to them.

Light is come - That is, Jesus, the Sun of righteousness, the fountain of light and life; diffusing his benign influences every where, and favoring men with a clear and full revelation of the Divine will.

Men loved darkness - Have preferred sin to holiness, Belial to Christ, and hell to heaven. חשך chashac, darkness, is frequently used by the Jewish writers for the angel of death, and for the devil. See many examples in Schoettgen.

Because their deeds were evil - An allusion to robbers and cut-throats, who practice their abominations in the night season, for fear of being detected. The sun is a common blessing to the human race - it shines to all, envies none, and calls all to necessary labor. If any one choose rather to sleep by day, that he may rob and murder in the night season, he does this to his own peril, and has no excuse: - his punishment is the necessary consequence of his own unconstrained actions. So will the punishment of ungodly men be. There was light - they refused to walk in it. They chose to walk in the darkness, that they might do the works of darkness - they broke the Divine law, refused the mercy offered to them, are arrested by Divine justice, convicted, condemned, and punished. Whence, then, does their damnation proceed? From Themselves.
Verse 20

For every one that doeth evil hateth the light - He who doth vile or abominable things: alluding to the subject mentioned in the preceding verse.

The word φαυλος, evil or vile, is supposed by some to come from the Hebrew פלס phalas, to roll, and so cover oneself in dust or ashes, which was practised in token of humiliation and grief, not only by the more eastern nations, see Job 42:6, but also by the Greeks and Trojans, as appears from Homer, Iliad xviii. l. 26; xxii. l. 414; xxiv. l. 640; compare Virgil, Aen. x. l. 844; and Ovid, Metam. lib. viii. l. 528. From the above Hebrew word, it is likely that the Saxon ful, the English foul, the Latin vilis, and the English vile, are derived. See Parkhurst under φαυλος.

Lest his deeds should be reproved - Or discovered. To manifest or discover, is one sense of the original word, ελεγχω, in the best Greek writers; and it is evidently its meaning in this place.
Verse 21

Wrought in God - In his presence, and through his assistance. This is the end of our Lord's discourse to Nicodemus; and though we are not informed here of any good effects produced by it, yet we learn from other scriptures that it had produced the most blessed effects in his mind, and that from this time he became a disciple of Christ. He publicly defended our Lord in the Sanhedrin, of which he was probably a member, Joh 7:50, and, with Joseph of Arimathea, gave him an honorable funeral, Joh 19:39, when all his bosom friends had deserted him. See Dodd.
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