And when the disciples heard it, they fell on their face, and were much afraid.
All Commentaries on Matthew 17:6 Go To Matthew 17
Cyril of Alexandria
AD 444
Through their speaking together it shows that the old prophets also spoke the same things as Jesus, even if enigmatically. In great awe the disciples fell on their faces, and the Savior raised them up. This shows that if Jesus had not been incarnate and had not been Mediator between God and humanity and strengthened his own nature, he would not have endured to hear the voice of God.