Jesus, and later also the apostles, have warned that after them false teachers will come who will deceive the flock, the congregation. This might trouble us, for how do we distinguish between a false teacher, a stranger (:5) and a true shepherd?
Jesus gives the answer, ‘The one who enters by the gate is the shepherd of the sheep’ (:2). And then He says, ‘I am the gate for the sheep’ (:7). So the true shepherd enters the congregation through Jesus. As Paul says, ‘For it is not the one who commends himself who is approved, but the one whom the Lord commends’ (2 Corinthians 10:18). Who claims to be a shepherd without the Lord’s recommendation, is someone who climbs in by some other way, and thus a thief. He seeks his own benefit, not that of the sheep.
These false teachers almost never enter through the gatekeepers, the elders of the congregation. False teachers always try to get a following behind their backs. And which kind of sheep follow them? The sheep who are prone to be deceived, because they do not know the voice of the Shepherd. The true sheep of the Shepherd know the voice of the Shepherd and they follow Him (:4).
He who has come to know the true Shepherd's voice will – if there is a thief - not follow him. Who loves God with all his heart, will immediately recognize if what is said is of God or of a thief. All who came to love God wholeheartedly belong to the adults in the congregation. They only long to do the will of God. Therefore they will always be able to distinguish whether someone speaks words of God or whether he came with his own empty, pious thoughts.