A teaching of Jesus' during The Sermon on the Mount

Jesus tells us that even though we may proclaim our faith and love for God, when we try to enter heaven he will say "I never knew you" and never let us in.

I think Jesus is reinforcing a central teaching with this message. If you love God in your heart, He will know. Simply going through the motions is as nothing compared to truly living your life well and loving others without reserve.