‘And behold, there appeared to them Moses and Elijah talking with him.'
And then to cap His glory Moses and Elijah appeared before the amazed eyes of the disciples and talked with Him. Men of Heaven came down to earth. ‘Behold' indicates something new that is happening of which note should be taken. His glorious Transfiguration had undoubtedly revealed His heavenly nature and status (compare John 17:5), but now the question is, what did the presence of Moses and Elijah reveal, and what did it mean? Note that they were ‘talking with Him'. It was not just to be seen as a series of strange visions, but as something that actually took place in which Moses and Elijah had a part to play.
It is quite possible that the disciples did not know who the visitors were at first, although it is equally possible that both Moses and Elijah wore things that identified them. Elijah's prophetic dress would certainly have been very distinctive. But their conversations would probably be the sealing factor.
Unquestionably the first significance of their presence is that it indicated that both the great Lawgiver of Israel, and the great representative of the Prophets who, as the greatest of all the prophets, was to return again to turn many to God (Malachi 4:5), were there to witness to Jesus. And they were both there in their heavenly state, supporting Jesus, and seeing Him as the central figure, and as the One to Whom they looked, and to Whom they offered their support. It confirms that both of them supported what Jesus was doing, and that in Him a greater than Moses, and a greater than Elijah (compare Matthew 12:41-42), had come, in order to ‘fulfil the Law or the Prophets' (Matthew 5:17). And that is no doubt what they were talking to Him about. In this regard it should be noted that the book of the Prophets had closed with the words ‘Remember you the law of Moses My servant --- behold I will send you Elijah the prophet' (Malachi 4:4-5). Now they were both there testifying to Jesus.
A further point that might be significant was that both of these men had previously gone into mountains for the very purpose of experiencing the mighty presence of God in person (Exodus 24:15; 1 Kings 19:8-18). And now here they were again in the mountain, but this time sharing in the glory of Jesus.
Matthew, like Luke, has reversed the order from ‘Elijah and Moses' as found in Mark. Part of the reason for this might have been in order to fit in with the order in Matthew 5:17. But it may also signify that as a Jew he is putting a greater emphasis on Moses. To the Jews Moses had an unparalleled pre-eminence.
However, the grounds for seeing a ‘second Moses' motif, rather than a second exodus motif, are not solid, unless we simply see by that that Jesus ‘fulfilled' both Moses and Elijah, and more. While there are superficial similarities to the book of Exodus they are not exact enough to indicate that. Jesus is not here to be seen as a second Moses nor as a second Elijah. He is greater than both and fulfils both, and both point to Him. In Him ‘Israel' are finally ‘coming out of Egypt' for good (Matthew 2:15). And we should note in this regard that Matthew deliberately omits the fact that they were speaking of His coming ‘exodus' (Luke 9:31) which He was to accomplish at Jerusalem, which would be strange if he particularly wanted to emphasise Jesus as a second, or even superior, Moses. Furthermore the reversal of the order actually makes it more difficult to see a pointer forward to a new Elijah (John), followed by a new Moses (Jesus) as lying behind the two names.
So what the presence of Moses and Elijah is accomplishing is the confirmation of Jesus' unique status as the One to whom they had pointed as representatives of the Law and the Prophets. They had pointed forward. He is the fulfilment of it all. And what Matthew's order may be intended to suggest is that he saw them as representing salvation history from its commencement to that time, with Moses as the great initial Deliverer, and Elijah as the final preparer of the way. And now the One has come for whom both have prepared, and they must point to Him and then withdraw. Their task is done. For Elijah's work has been completed by John the Baptist. But none of the three disciples would ever forget that they had seen these great men bear witness to their Master. It threw new light onto many things.
But there is possibly a further significance in the mentioning of these two, for Moses was the one who originally formed ‘the congregation of Israel' into a cohesive unit, and miraculously fed them with bread in the wilderness, and Elijah had been responsible in the northern kingdom of Israel for establishing ‘the sons of the prophets' and for taking care of the seven thousand who had not bowed the knee to Baal whom God had reserved to Himself (1 Kings 19:18), who represented what was left of the congregation of Israel that was still acceptable to God, thereby establishing a new ‘congregation' from the remnant. And he also miraculously fed a woman and her son with bread (1 Kings 17:12-16), while his successor too, who shared his spirit (2 Kings 2:9; 2 Kings 2:15), miraculously fed a hundred of his followers with bread (2 Kings 4:42-44, compare Matthew 4:1-7). Thus these two may be seen as pointing ahead to the One who will form and miraculously feed in a far greater way the final new ‘congregation of Israel', preserved out of the old.