Bede the Venerable — as excerpted in the Catena Aurea on Mark 12:13-17

“(ubi sup.) A denarius was a piece of money, accounted equal to ten smaller coins, and bearing the image of Cæsar; wherefore there follows: And he saith unto them, Whose is this image and superscription? And they said unto him, Cæsar’s. Let those who think that our Saviour asked the question through ignorance and not by an economy, learn from this that He might have known whose image it was; but He puts the question, in order to return them a fitting answer; wherefore there follows: And Jesus answering said unto them, Render unto Cæsar the things that are Cæsar’s, and unto God the things that are God’s.”