John Calvin on Matthew 21:8

8. And a very great multitude. Here the Evangelists relate that Christ was acknowledged as a king by the people. It might, indeed, appear to be a ludicrous exhibition, “Vray est qu’il pouvoit sembler que c’estoit un ieu de petits enfans;” — “true, it might be thought that it was a game of little children.” that a multitude of obscure persons, by cutting down trees, and strawing their garments, bestowed on Christ the empty title of King; but as they did this in good earnest, and as they gave an honest testimony of their reverence, so Christ looked upon them as fit heralds of his kingdom. Nor ought we to wonder at such a beginning, when even in the present day, while sitting at the right hand of the Father, he commissions from the heavenly throne obscure men, by whom his majesty is celebrated in a despicable manner. I do not think it probable that the branches of palm-trees were cut down, as some interpreters conjecture, in accordance with an ancient and solemn rite appointed for that day. On the contrary, it would seem to have been by a sudden movement of the Spirit that this honor was rendered to Christ, when nothing of this nature had been intended by the disciples, whom the rest of the multitude imitated by doing the same thing; for this also may be inferred from the words of Luke.