1 John 2:18-19

18My children, the world will soon end. You have heard that the enemy of Christ will appear. You can see that many enemies of Christ have already appeared. This shows us that the world will end soon.

19These people used to be in our group of believers. But they left us. They never really belonged to our group. If they had been true believers, they would have remained with us. When they left us, it showed clearly that none of them really belonged to us.