3:16-21 Here is the condescension, the miracle, the mystery of Divine love, that God would redeem the church with his own blood. Surely we should love those whom God has loved, and so loved. The Holy Spirit, grieved at selfishness, will leave the selfish heart without comfort, and full of darkness and terror. By what can it be known that a man has a true sense of the love of Christ for perishing sinners, or that the love of God has been planted in his heart by the Holy Spirit, if the love of the world and its good overcomes the feelings of compassion to a perishing brother? Every instance of this selfishness must weaken the evidences of a man's conversion; when habitual and allowed, it must decide against him. If conscience condemn us in known sin, or the neglect of known duty, God does so too. Let conscience therefore be well-informed, be heard, and diligently attended to.

19. hereby—Greek, "herein"; in our loving in deed and in truth (1Jo 3:18).

we know—The oldest manuscripts have "we shall know," namely, if we fulfil the command (1Jo 3:18).

of the truth—that we are real disciples of, and belonging to, the truth, as it is in Jesus: begotten of God with the word of truth. Having herein the truth radically, we shall be sure not to love merely in word and tongue. (1Jo 3:18).

assure—literally, "persuade," namely, so as to cease to condemn us; satisfy the questionings and doubts of our consciences as to whether we be accepted before God or not (compare Mt 28:14; Ac 12:20, "having made Blastus their friend," literally, "persuaded"). The "heart," as the seat of the feelings, is our inward judge; the conscience, as the witness, acts either as our justifying advocate, or our condemning accuser, before God even now. Joh 8:9, has "conscience," but the passage is omitted in most old manuscripts. John nowhere else uses the term "conscience." Peter and Paul alone use it.

before him—as in the sight of Him, the omniscient Searcher of hearts. Assurance is designed to be the ordinary experience and privilege of the believer.