2 John 1:2; 2 John 1:7; 2 John 1:10

2 For the truth's sake, which dwelleth in us, and shall be with us for ever.
7 For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist.
10 If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed :