2 in this know ye the Spirit of God; every spirit that doth confess Jesus Christ in the flesh having come, of God it is, 3 and every spirit that doth not confess Jesus Christ in the flesh having come, of God it is not; and this is that of the antichrist, which ye heard that it doth come, and now in the world it is already.
4 Ye—of God ye are, little children, and ye have overcome them; because greater is He who 'is' in you, than he who is in the world. 5 They—of the world they are; because of this from the world they speak, and the world doth hear them;
Matthew Henry's Commentary on 1 John 4:2-5
Commentary on 1 John 4:1-6
(Read 1 John 4:1-6)
Christians who are well acquainted with the Scriptures, may, in humble dependence on Divine teaching, discern those who set forth doctrines according to the apostles, and those who contradict them. The sum of revealed religion is in the doctrine concerning Christ, his person and office. The false teachers spake of the world according to its maxims and tastes, so as not to offend carnal men. The world approved them, they made rapid progress, and had many followers such as themselves; the world will love its own, and its own will love it. The true doctrine as to the Saviour's person, as leading men from the world to God, is a mark of the spirit of truth in opposition to the spirit of error. The more pure and holy any doctrine is, the more likely to be of God; nor can we by any other rules try the spirits whether they are of God or not. And what wonder is it, that people of a worldly spirit should cleave to those who are like themselves, and suit their schemes and discourses to their corrupt taste?