Sermon by St. Ambrose the Bishop
The Lord went up to the temple, and left the Jews behind. And this was fitting, for he was about to take up his abode in the hearts of the Gentiles. The true temple of God, wherein he worshipped, not in the deadness of the letter, but in spirit and in truth, is that temple whereof the foundations are laid, not in courses of stone, but in acts of faith. He leaveth behind him such as hate him, and getteth him to such as will love him. And so he cometh unto the Mount of Olives, that he may plant upon the heights of virtue those young olive-branches, whose mother is the Jerusalem which is above. Upon this mountain standeth he, the heavenly husbandman, that all they which be planted in the house of the Lord may be able each one to say: As for me, I am like a green olive-tree in the house of God.
But we may even think of this mountain as being Christ himself. For what other beareth such plants as he doth, not weighted down with an abundance of earthly fruit, but spiritually fruitful with the fulness of the Gentiles? He also it is by whom we go up, and unto whom we go up. He is the Door. He is the Way. For he is the one which is opened and which openeth. Unto him, whosoever entereth in, knocketh. Unto him also, having entered, to obtain their reward, they do offer their worship. A figure also was it that the disciples went into a village, and that there they found an ass tied and a colt with her; neither could they be loosed, save at the hand of his Apostles which loosed them. He whose work and life are like theirs will have such grace as was theirs. Be thou also such as they, if thou wouldest loose them that are bound.
Now consider how those two who were convicted of transgression, and banished from the freedom of the Paradise of Eden, were made to be dwellers in towns, bound over as it were, into a village; and in this observe how Life called back again them whom death had cast out. For this reason, we read in Matthew that there were tied both an ass and her colt. Both male and female were banished from Eden. The she-ass and the male-colt doth put us in mind of the return to Paradise. The she-ass mindeth us of our sinful Mother Eve, and the colt of the multitude of the Gentiles. Upon the colt Christ took his seat. And thus it is well written of the colt, that thereon never yet had man sat, for no man before Christ ever called the Gentiles into the Church, which statement thou hast in Mark who saith: Whereon never man sat.