And after six days Jesus took with him Peter, and James, and John, and led them up into a high mountain apart by themselves: and he was transfigured before them.
All Commentaries on Mark 9:2 Go To Mark 9
Tertullian of Carthage
AD 220
While, in the revelation of His own glory, He prefers, from among so many saints and prophets, to have with him Moses and Elias