I write unto you, fathers, because ye have known him that is from the beginning. I write unto you, young men, because ye have overcome the wicked one. I write unto you, little children, because ye have known the Father.
All three classes are first addressed in the present, "I write;" then in the aorist х egrapsa (G1125)], 'I wrote.' Moreover, in 'Aleph (') A B C, in the end of 1 John 2:13, 'I wrote,' not "I write." Two classes, "fathers" and "young men," are addressed with the same words each time (except that the address to the young men has an addition, expressing the source of their victory); but the 'little sons' and "little children" are differently addressed, as 'little sons' includes all three classes.
Have known - and do know: so the perfect means. The 'I wrote' refers not to a former letter, but to this. It was an idiom to put the past, regarding the time from the reader's point of view: when he should receive the letter the writing would be past. When he uses "I write," he speaks from his own point of view.
Him that is from the beginning - Christ: 'that which was from the beginning.'
Overcome. The fathers, appropriately to their age, are characterized by knowledge. The young men, appropriately to theirs, by activity in conflict. The fathers, too, have conquered; but now their active service is past, and they and the children alike are characterized by knowing (the fathers know Christ, 'Him that was from the beginning;' the children know the Father). The first thing that the little children realize is that God is their Father; corresponding in the parallel clause to 'little sons ... your sins are forgiven you for His name's sake'-the universal privilege of all those really dear sons of God. Thus this latter includes all, whereas the former refers to these especially in the first stage of spiritual life, "little children." Of course these can only know the Father as theirs through the Son (Matthew 11:27). It is beautiful to see how the fathers are characterized as reverting to the first great truth of spiritual childhood, the ripest fruit of advanced experience, the knowledge of him that was from the beginning (twice, 1 John 2:13-14). Many of them had probably known Jesus in person, as well as by faith.
Young men ... strong - made so out of natural weakness, hence, enabled to overcome 'the strong man armed,' through Him that is 'stronger' (Hebrews 11:34). Faith is the victory that overcomes the world. "Overcome" is peculiarly John's term, adopted from his loved Lord (John 16:33). It occurs sixteen times in the Apocalypse, six times in the first letter, only thrice in the rest of the New Testament. In order to overcome the world on the ground of the blood of the Saviour, we must be willing, like Christ, to pert with whatever of the world belongs to us: whence immediately after 'ye have overcome (and are overcoming: perfect) the wicked one (the prince of the world),' it is added, "Love not the world, neither the things ... in the world."
And ... - the secret of the young men's strength: the Gospel word clothed with living power by the Spirit who abideth permanently in them. This is "the sword of the Spirit" wielded in prayerful waiting on God. Contrast the mere physical strength of young men, Isaiah 40:30-31. Oral teaching prepared them for the profitable use of the word when written. 'Antichrist cannot endanger you (1 John 2:18), nor Satan tear from you the word of God.'
The wicked one - who, as "prince of this world," enthralls it (1 John 2:15-17; 1 John 5:19, Greek, "the wicked one"), especially the young. Christ came to destroy him (1 John 3:8). Believers achieve the first conquest over him when they pass from darkness to light; but afterward they need to maintain a continual keeping of themselves from his assaults, looking to God, by whom alone they are kept safe. Bengel thinks John refers to the remarkable constancy exhibited by youths in Domitian's persecution. Also to the young man whom John, after his return from Patmos, led, with loving persuasion, to repentance. This youth had been commended by John, in one of his apostolic tours, as a promising disciple to the overseers of the Church: he had been, therefore, carefully watched up to baptism. But afterward, relying too much on baptismal grace, he joined evil associates, and fell from step to step down, until he became a captain of robbers. When John, some years after, revisited that church, and heard of it, he hastened to the retreat of the robbers, suffered himself to be seized, and taken into the captain's presence. The youth, stung by conscience, fled away from the venerable apostle. Full of love, the aged father ran after him, called on him to take courage, and announced to him forgiveness of his sins in the name of Christ. The youth was recovered to Christianity, and induced many of his bad associates to repent and believe (Clemens Alexandrinus, 'Quis dives salvus?' 100: 4:, 2).