Gregory the Dialogist : "Their fathers have transgressed my covenant unto this day, and the sons are of hard face and indomitable heart, to whom I send you." Behold, there is one fault of pride, because they have transgressed the covenant. Behold, another of obstinacy, because even unto this day. Behold, in the iniquity of the sons there is the grave fault of imprudence, because they are of a hard face, since they no longer blush at the evils they do, and never return to repentance even after their faults, because they are of an untamable heart. But when those to whom the prophet is sent are of such great depravity and such great obstinacy, who does not already see that the person of the prophet can be despised by such perverse men? But behold, authority is given to his person, when it is added: "And you shall say to them: Thus says the Lord God." As if it were openly said: Because you will be despised on your own account, it is necessary that you speak from my voice. Lest you yourself who are sent be held in contempt; bringing forth my words, show who sent you. — Homilies on Ezekiel, Book 1, Homily 9 Jerome : (Verse 4.) And they are sons with a fierce face and an untamed heart, to whom I send you. This is not found in the Septuagint. It is of great mercy to send God to such people and not to despair of their salvation; and it is prophetic confidence that he is not afraid to go to such people as well. But we must understand that with an untamed heart and a fierce face, we should accept what is said to the sinner: Your neck is an iron sinew and your forehead is bronze (Isaiah 48:6). And those who are accused of having a heart of stone in their subsequent actions, God says that He will uproot them and restore them with a heart of flesh, so that they may receive God's commands through His gentleness. — Commentary on Ezekiel