Catena Aurea on Matthew 16:24–25: Gregory the Great

There are two ways of taking our cross; when the body is afflicted by abstinence, or when the heart is pained by compassion for another. Forasmuch as our very virtues are beset with faults, we must declare that vainglory sometimes attends abstinence of flesh, for the emaciated body and pale countenance betray this high virtue to the praise of the world. Compassion again is sometimes attended by a false affection, which is hereby led to be consenting unto sin; to shut out these, He adds, “and follow me.”