Luke 9:30
And, behold, there talked with him two men, which were Moses and Elias:
Cross-reference
Luke 9:19 records speculation that Jesus was Elijah; here Elijah himself appears, revealing the truth.
In Luke 24:27, Jesus interprets Moses and the prophets as pointing to himself, exactly the two figures appearing here to discuss his departure.
In Luke 24:44, Jesus says all Scripture (Law, Prophets, Psalms) must be fulfilled in him, represented by Moses and Elijah here.
Matthew 17:3 is the parallel account of the same transfiguration event, confirming Moses and Elijah appeared with Jesus.
Matthew 17:4 shows Peter's impulsive offer to build tents, revealing his misunderstanding of the moment's significance.
Mark 9:4-6 provides the same scene with added detail of Peter's confusion and their fear, enriching the account.
Malachi 4:5 prophesies Elijah's coming before the Lord; here Elijah appears at the Transfiguration, a partial fulfillment.
1 Kings 17:1 introduces Elijah's prophetic ministry; here he appears with Moses, representing the prophets.