At the same time there appeared talking to him Moses and Elijah, the great representatives of the Law and the Prophets on which the Jewish religion was founded.  Peter, scarcely knowing what he was saying, suggested making three booths or tents, hoping in this way to prolong the supernatural and awesome experience on the mountain slopes.

But at that moment a cloud of Divine glory enveloped them and they heard a voice from the cloud saying, “This my Son, my Chosen; listen to him!” (NRSV, Luke 9:35).  And then the cloud disappeared and they no longer saw anyone with them but Jesus only.  

Once before that Divine voice had spoken – at his Baptism in Jordan – and then it had set the seal of the Father’s approval upon his Son’s hidden life at Nazareth: “You are my Son, the Beloved; with you I am well pleased” (NRSV, Mark 1:11).  Now it did so upon his ministry up to that moment, and especially upon his recently declared willingness to offer himself upon the Cross for us and for our salvation.  And so later on, when he had made that perfect offering, the Resurrection set the seal of his Father’s approval upon his whole obedient life and death.