2 John

2 John 1
The only epistle addressed to a sister. Because “many deceivers are entered into the world” the aged apostle warns her against receiving any who bring not the true doctrine as to Christ. True love is accompanied by obedience to the truth and proof that the work is of God. There is no room for adding anything to the revelation God has given nor for compromising it.
Written after A.D. 90.