On Mount Tabor, Elijah heard from God, as a still small voice. On the same mountain, many years earlier, Moses also heard from God, from the midst of a burning bush. These are the two men present with Jesus, at the same time, when he was transfigured.... on a mountain. This time, Moses and Elijah were not men of flesh and blood, but spirits, while the Word of God was now in a physical body.

http://filsofia.com/share/20260901-transfiguration.mp4

They heard the Word of God on Mount Tabor, and many years later Jesus was visibly with them. Jesus is the Word of God. He was a bright, shining light, like the fire that Moses saw in the bush.

Jesus is that same Word of God that previously spoke in previous generations, and to Moses and Elijah.