By this you know the Spirit of God: every spirit who confesses that Jesus Christ has come in the flesh is of God, and every spirit who doesn’t confess that Jesus Christ has come in the flesh is not of God; and this is the spirit of the Antichrist, of whom you have heard that it comes. Now it is in the world already.
See how great a love the Father has given to us, that we should be called children of God! For this cause the world doesn’t know us, because it didn’t know him.