Mark 9:2-10

Six days after this, Jesus took with Him Peter and James and John and led them up on a high mountain apart by themselves. And He was transfigured before them and became resplendent with divine brightness. And His garments became glistening, intensely white, as no fuller (cloth dresser, launderer) on earth could bleach them. And Elijah appeared [there] to them, accompanied by Moses, and they were holding [a protracted] conversation with Jesus. And Peter took up the conversation, saying, Master, it is good and suitable and beautiful for us to be here. Let us make three booths (tents)–one for You and one for Moses and one for Elijah. For he did not [really] know what to say, for they were in a violent fright (aghast with dread). And a cloud threw a shadow upon them, and a voice came out of the cloud, saying, This is My Son, the [most dearworthy] Beloved One. Be constantly listening to and obeying Him! And looking around, they suddenly no longer saw anyone with them except Jesus only. And as they were coming back down the mountain, He admonished and expressly ordered them to tell no one what they had seen until the Son of Man should rise from among the dead. So they carefully and faithfully kept the matter to themselves, questioning and disputing with one another about what rising from among the dead meant.