The three disciples that witnessed the Transfiguration of Jesus were

The three disciples who witnessed the Transfiguration of Jesus were Peter, James, and John. This is recorded in all three Synoptic Gospels: Matthew 17:1-8, Mark 9:2-8, and Luke 9:28-36.

Jesus took these three disciples up a high mountain (traditionally identified as Mount Tabor or Mount Hermon), where He was transfigured before them. His face shone like the sun, and His clothes became dazzling white. Moses and Elijah appeared and spoke with Jesus, and a voice from a cloud declared, "This is my beloved Son, with whom I am well pleased; listen to him."

Peter, James, and John formed an inner circle among the twelve apostles and were present at several key events that the other disciples did not witness, including the raising of Jairus's daughter (Mark 5:37) and Jesus's agony in the Garden of Gethsemane (Matthew 26:37). Andrew, though Peter's brother and one of the first disciples called, was not part of this inner group at these events. Matthew was also not present at the Transfiguration.