BibleGateway: 1 John 4:1-5
1 Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world. 2 Hereby know ye the Spirit of God: Every spirit that confesseth that Jesus Christ is come in the flesh is of God: 3 And every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world.
4 Ye are of God, little children, and have overcome them: because greater is he that is in you, than he that is in the world. 5 They are of the world: therefore speak they of the world, and the world heareth them.(KJV)