41 My dear friends, don't believe everything you hear. Carefully weigh and examine what people tell you. Not everyone who talks about God comes from God. There are a lot of lying preachers loose in the world. 2 Here's how you test for the genuine Spirit of God. Everyone who confesses openly his faith in Jesus Christ - the Son of God, who came as an actual flesh-and-blood person - comes from God and belongs to God. 3 And everyone who refuses to confess faith in Jesus has nothing in common with God. This is the spirit of antichrist that you heard was coming. Well, here it is, sooner than we thought!
Matthew Henry's Commentary on 1 John 4:1-3
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?