The Transfiguration, in the New Testament, is an event traditionally understood as the revelation of the glory of Jesus Christ as the son of God. Described in Matthew 17, Mark 9, and Luke 9, it occurs when Jesus takes his disciples Peter, James, and John to a "high mountain" (traditionally, Mount Tabor): "And he was transfigured before them, and his face shone like the sun, and his garments became white as light" (Matthew 17:2). At the same time, the prophets Moses and Elijah appeared to the disciples and a "voice from the cloud" said, "This is my beloved Son, with whom I am well pleased; listen to him" (Matthew 17:5).

The Feast of the Transfiguration originated in the Eastern church before the 7th century and was gradually introduced into the Western church. Its general observance in the Western church was established in 1456 by Pope Callistus III, who fixed its date as August 6 to commemorate a Christian victory over the Ottoman Turks at Belgrade.