Hilary of Poitiers
Catena Aurea · Matthäusevangelium 21
And when they drew nigh unto Jerusalem, and were come to Bethphage, unto the mount of Olives, then sent Jesus two disciples, Saying unto them, Go into the village over against you, and straightway ye shall find an ass tied, and a colt with her: loose them, and bring them unto me. And if any man say ought unto you, ye shall say, The Lord hath need of them; and straightway he will send them. And this was done, that it might be fulfilled which was spoken by the prophet, saying, Tell ye the daughter of Sion, Behold, thy King cometh unto thee, meek, and sitting upon an ass, and a colt the foal of an ass. And the disciples went, and did as Jesus commanded them, And brought the ass, and the colt, and put on them their clothes, and they set him thereon. And a very great multitude spread their garments in the way; others cut down branches from the trees, and strawed them in the way. And the multitudes that went before, and that followed, cried, saying, Hosanna to the Son of David: Blessed is he that cometh in the name of the Lord; Hosanna in the highest.
Or by the ass and the colt is shewn the twofold calling from among the Gentiles. For the Samaritans did serve after a certain fashion of obedience, and they are signified by the ass; but the other Gentiles wild and unbroken are signified by the colt. Therefore two are sent to loose them that are bound by the chains of error; Samaria believed through Philip, and Cornelius as the first-fruits of the Gentiles was brought by Peter to Christ.