All three Synoptic Gospels tell the story of the Transfiguration (Matthew 17:1-8; Mark 9:2-9; Luke 9:28-36). With remarkable agreement, all three place the event shortly after Peter’s confession of faith that Jesus is the Messiah and Jesus’ first prediction of his passion and death. Peter’s eagerness to erect tents or booths on the spot suggests it occurred during the Jewish weeklong, fall Feast of Booths.In spite of the texts’ agreement, it is difficult to reconstruct the disciples’ experience, according to Scripture scholars, because the Gospels draw heavily on Old Testament descriptions of the Sinai encounter with God and prophetic visions of the Son of Man. Certainly Peter, James and John had a glimpse of Jesus’ divinity strong enough to strike fear into their hearts. Such an experience defies description, so they drew on familiar religious language to describe it. And certainly Jesus warned them that his glory and his suffering were to be inextricably connected—a theme John highlights throughout his Gospel.
Tradition names Mt. Tabor as the site of the revelation. A church first raised there in the fourth century was dedicated on August 6. A feast in honor of the Transfiguration was celebrated in the Eastern Church from about that time. Western observance began in some localities about the eighth century.
On July 22, 1456, Crusaders defeated the Turks at Belgrade. News of the victory reached Rome on August 6, and Pope Callistus III placed the feast on the Roman calendar the following year.