1 John 2:19-21
19 These “against-Christ” people used to be members of our churches, but they never really belonged with us or else they would have stayed. When they left us it proved that they were not of us at all.
20 But you are not like that, for the Holy Spirit has come upon you, and you know the truth. 21 So I am not writing to you as to those who need to know the truth, but I warn you as those who can discern the difference between true and false.Read full chapter