What Is Transfiguration in the Bible?
Feast
When Jesus, on a mountain, became radiant in front of Peter, James, and John.
Today
It is celebrated on August 6.
Where it appears in the Bible
Matthew 17:1-2
What the Bible says
Matthew 17:1-2
1And after six days Jesus taketh unto him Peter and James, and John his brother, and bringeth them up into a high mountain apart: 2And he was transfigured before them. And his face did shine as the sun: and his garments became white as snow.
Douay-Rheims Bible (Challoner revision), public domain.
Source: Catechism 554-556