Jerome
Catena Aurea · Matthäusevangelium 19
His disciples say unto him, If the case of the man be so with his wife, it is not good to marry. But he said unto them, All men cannot receive this saying, save they to whom it is given. For there are some eunuchs, which were so born from their mother’s womb: and there are some eunuchs, which were made eunuchs of men: and there be eunuchs, which have made themselves eunuchs for the kingdom of heaven’s sake. He that is able to receive it, let him receive it.
He speaks of three kinds of eunuchs, of whom two are carnal, and one spiritual. One, those who are so born of their mother’s womb; another, those whom enemies or courtly luxury has made so; a third, those who have made themselves so for the kingdom of heaven, and who might have been men, but become eunuchs for Christ. To them the reward is promised, for to the others whose continence was involuntary, nothing is due.