v. 14, 15 — And Jesus, having found a young ass, sat thereon; as it is written, Fear not, daughter …

For when a great multitude were escorting Him like a body-guard and shouting His praises, with the most perfect self-restraint He seated Himself upon an ass, teaching us not to be lifted up by praises, and omitting no necessary thing. Matthew therefore related at greater length the circumstances concerning the ass; but John comes at once to the point of the affair that was most suited to the occasion, as it is his custom to do. And since, contrary to His usual habits, on this occasion only, Christ appears seated on an ass, we do not say that He so sat for the reason that it was a long distance to the city; for it was not more than fifteen furlongs off: nor because there was a multitude; for it is certain that on other occasions when He was found with a multitude He did not do this: but He does so, to indicate that He is about to make subject to Himself as a new people the unclean among the Gentiles, and to lead them up to the prerogative of righteousness, and to the Jerusalem above, of which the earthly is a type; into which this people being made clean shall enter with Christ, Who will be hymned by the guileless angels, of whom the babes are a type. And He calls the ass a colt, because the people of the Gentiles had been untrained to the piety which faith produces.

CyrJn 8.14.1