Matthew 21:7

And put on them their clothes - Thus acknowledging him to be their king, for this was a custom observed by the people when they found that God had appointed a man to the kingdom. When Jehu sat with the captains of the army, and Elisha the prophet came, by the order of God, to anoint him king over Israel, as soon as he came out of the inner chamber into which the prophet had taken him to anoint him, and they knew what was done, every man took his garment, and spread it under him on the top of the steps, and blew the trumpets, saying, "Jehu is king." 2 Kings 9:13.

And they set him thereon - Και επεκαθισεν επανω αυτων, and he sat upon them; but instead of επανω αυτων, upon Them, the Codex Bezae, seven copies of the Itala, some copies of the Vulgate, and some others, read επ' αυτον, upon him, i.e. the colt. This is most likely to be the true reading; for we can scarcely suppose that he rode upon both by turns, - this would appear childish; or that he rode upon both at once, for this would be absurd. Some say he sat on both; for "the ass that was tied up was an emblem of the Jews bound under the yoke of the law; and the colt that had not been tied represented the Gentiles who were not under the law; and that Jesus Christ's sitting on both represented his subjecting the Jews and the Gentiles to the sway of his evangelical scepter." He who can receive this saying, let him receive it.

And put on them their clothes - This was done as a token of respect, 2 Kings 9:13.

21:7 They set him thereon - That is, on the clothes.