I John 1:6 If we say that we have fellowship with Him (Jesus) and yet walk in the darkness, we lie and do not practice the truth.
I John 2:17 And the world is passing away, and also its lust; but the one who does the will of God abides forever.
I John 2:18-19 Children, it is the last hour; and just as you heard that antichrist is coming, even now many antichrist have arisen; from this we know that it is the last hour.
Verse 19 They went out from us, but they were not really of us; for if they been of us, they would have remained with us (faking the new life); but they went out, in order that it might be shown that they all are not of us.
(NAS)