Origen's Commentary on the Gospel of Matthew

But another might say that the perfect man is here called little, applying the word, “For he that is least among you all, the same is great,” and will affirm that he who humbles himself and becomes a child in the midst of all that believe, though he be an apostle or a bishop, and becomes such “as when a nurse cherisheth her own children,” is the little one pointed out by Jesus, and that the angel of such an one is worthy to behold the face of God. For to say that the little are here called perfect, according to the passage, “He that is least among you all, the same is great,” and as Paul said, “Unto me who am less than the least of all saints was this grace given,” will seem to be in harmony with the saying, “Whoso shall cause one of these little ones to stumble,” and “So it is not the will of My Father in heaven, that one of these little ones should perish.” For he, as has been stated, who is now little, could not be made to stumble nor perish, for “great peace have they who love the law of God, and there is no stumbling-block to them;” and he could not perish, who is least of all among all the disciples of Christ, and on this account becomes great; and, since he could not perish, he could say, “Who shall separate us from the love,” etc. But he who wishes to maintain this last exposition will say that the soul even of the just man is changeable, as Ezekiel also testifies, saying, that the righteous man may abandon the commandments of God, so that his former righteousness is not reckoned unto him; wherefore it is said, “Whoso shall cause to stumble one of these little ones, and, “It is not the will of My Father which is in heaven that one of these little ones should perish.”

[As for the exposition of the matters relating to “the hundred sheep,” you may consult the homilies on Luke.]