Jerome
Catena Aurea · Matthäusevangelium 10
Behold, I send you forth as sheep in the midst of wolves: be ye therefore wise as serpents, and harmless as doves. But beware of men: for they will deliver you up to the councils, and they will scourge you in their synagogues; And ye shall be brought before governors and kings for my sake, for a testimony against them and the Gentiles.
Wise, that they might escape snares; simple, that they might not do evil to others. The craft of the serpent is set before them as an example, for he hides his head with all the rest of his body, that he may protect the part in which life is. So ought we to expose our whole body, that we may guard our head which is Christ; that is, that we study to keep the faith whole and uncorrupt.