Shortly before the Transfiguration it had been revealed to St Peter that Jesus was the Messiah, the Son of the living God, and the apostle had declared that truth in the presence of the Twelve.  Now God’s own voice confirmed that he was indeed his Beloved Son to whom all Divine authority had been committed.  The Jewish religion had now fulfilled its purpose by preparing for the coming of Our Blessed Lord, and so Moses and Elijah, its great representatives departed, leaving Jesus only, God’s own revelation of himself.  The Law and the prophets gave place to the Gospel – it was now, “Listen to him”.

Immediately after Peter’s declaration that he was the Messiah, the Son of the living God, Jesus had given his Apostles their first warning of his Cross and Passion.  According to Jewish belief contained in the Book of Deuteronomy, everyone who was hanged or crucified was accursed by God.  It was therefore necessary that they should be prepared beforehand in a vivid and unforgettable way, for his Crucifixion and Resurrection, and might be assured beyond all doubt that Christ, though rejected by human beings, was approved and accepted by God, so that they could confidently face and overcome all opposition to the Gospel.