{19} They went out from us, but they were not of us; for if they had been of us, {o} they would no doubt have continued with us: {20} but they went out, that they might be made manifest that they were not all of us.

(19) A digression against certain offences and stumbling blocks at which that young age especially might stumble and be shaken, Therefore that they should not be terrified with the falling back of certain, first he makes plain to men that although those who fall from God and his religion had a place in the Church, yet they were never of the Church: because the Church is the company of the elect, who cannot perish, and therefore cannot fall from Christ.

(o) So then the elect can never fall from grace.

(20) Secondly, he shows that these things happen to the benefit of the Church, that hypocrites may be plainly known.

People's New Testament

2:19 They went out from us, but they were not of us. This implies that these antichrists were apostates. The worst men are often those who were once outwardly religious and have fallen away.

For if they had been of us, they would no doubt have continued with us. Had they been true and genuine Christians they could hardly have fallen into such a state of enmity. Their going away and bitter opposition show that they were not real converts.

Wesley's Notes

2:19 They were not of us - When they went; their hearts were before departed from God, otherwise, they would have continued with us: but they went out, that they might be made manifest - That is, this was made manifest by their going out.

Scofield Reference Notes

[3] went out from us

"Went out from us," that is, doctrinally. Doubtless then, as now, the deniers of the Son 1Jn 2:22,23 still called themselves Christians. Cf 2Tim 1:15.

Jamieson-Fausset-Brown Bible Commentary

19. out from us-from our Christian communion. Not necessarily a formal secession or going out: thus Rome has spiritually gone out, though formally still of the Christian Church.

not of us-by spiritual fellowship (1Jo 1:3). "They are like bad humors in the body of Christ, the Church: when they are vomited out, then the body is relieved; the body of Christ is now still under treatment, and has not yet attained the perfect soundness which it shall have only at the resurrection" [Augustine, Ten Homilies on the First Epistle of John, Homily 3.4].

they would . have continued-implying the indefectibility of grace in the elect. "Where God's call is effectual, there will be sure perseverance" [Calvin]. Still, it is no fatal necessity, but a "voluntary necessity" [Didymus], which causes men to remain, or else go from the body of Christ. "We are either among the members, or else among the bad humors. It is of his own will that each is either an Antichrist, or in Christ" [Augustine]. Still God's actings in eternal election harmonize in a way inexplicable to us, with man's free agency and responsibility. It is men's own evil will that chooses the way to hell; it is God's free and sovereign grace that draws any to Himself and to heaven. To God the latter shall ascribe wholly their salvation from first to last: the former shall reproach themselves alone, and not God's decree, with their condemnation (1Jo 3:9; 5:18).

that they were not all of us-This translation would imply that some of the Antichrists are of us! Translate, therefore, "that all (who are for a time among us) are not of us." Compare 1Co 11:19, "There must be heresies among you, that they which are approved may be made manifest among you." For "were" some of the oldest manuscripts read "are." Such occasions test who are, and who are not, the Lord's people.

Matthew Henry's Concise Commentary

2:18-23 Every man is an antichrist, who denies the Person, or any of the offices of Christ; and in denying the Son, he denies the Father also, and has no part in his favour while he rejects his great salvation. Let this prophecy that seducers would rise in the Christian world, keep us from being seduced. The church knows not well who are its true members, and who are not, but thus true Christians were proved, and rendered more watchful and humble. True Christians are anointed ones; their names expresses this: they are anointed with grace, with gifts and spiritual privileges, by the Holy Spirit of grace. The great and most hurtful lies that the father of lies spreads in the world, usually are falsehoods and errors relating to the person of Christ. The unction from the Holy One, alone can keep us from delusions. While we judge favourably of all who trust in Christ as the Divine Saviour, and obey his word, and seek to live in union with them, let us pity and pray for those who deny the Godhead of Christ, or his atonement, and the new-creating work of the Holy Ghost. Let us protest against such antichristian doctrine, and keep from them as much as we may.