Mark 9:4

ὤφθη. The word used of the appearances of Christ after the Resurrection (Luke 24:34; Acts 9:17; Acts 13:31; Acts 26:16; 1 Corinthians 15:5-8). The three were thoroughly awake (Luke 9:32). The ὅραμα (Matthew 17:9) was no dream.

Ἠλείας σὺν Μωυσεῖ. Mt. and Lk. have “Moses and Elijah,” which is the more natural order. But Elijah was expected to return (Mark 6:15; Mark 8:28), whereas Moses was an unexpected addition; hence Mk’s expression. The possible reappearance of Moses seems to have been a later idea of the Jews. In spite of Deuteronomy 34:5 and Joshua 1:1-2, it was believed that he was taken up to heaven alive (Assumption of Moses). The power to recognize these representatives of the Law and the Prophets is analogous to that of St Paul recognizing Ananias in a vision (Acts 9:12). The recognition was necessary for the purposes of the Transfiguration, and it might confirm them in the belief that Christ was not overturning the Law and the Prophets, for the representatives of both were in conference with Him. “The Law and the Prophets paid homage to the Gospel” (Loisy).