To Florus 3.41

He therefore says that these two things show God cannot lie: the fact that he promised, and the fact that he calls himself to witness that he will fulfill his promise. This does not mean that God’s word is normally weak or doubtful without such an attestation. Rather, to load his truth with weighty proofs, he adopted the kind of speech that makes even people accustomed to deceiving others believable. With this same weight God warns and commands in the present case: no one among his people should suspect what the advocates of inherited sin assert, and everyone should understand that God cannot judge in the way he condemns. ‘As I live, says the Lord God, this proverb shall no longer be spoken in Israel’ (Ezekiel 18:3).