Jeremias 4
Theodoret of Cyrus · Comentário Patrístico (catena)
Jeremias 4:2
"If you swear, 'The Lord lives,' in truth, in justice and in righteousness." In the sacred Gospels, by contrast, he made more perfect prescriptions than these: "It was said to the ancients, You shall not swear falsely: you shall discharge your oaths to the Lord. But I tell you, do not swear at all." He bids Jews, being weak as they are, to swear by him so that through the habit of swearing they may learn to adore him alone. He also promises that if this is done, "nations will be blessed through him and through him will praise God in Jerusalem." In other words, when they practiced true worship of God, many of the neighboring peoples would learn about godliness. — ON JEREMIAH 1:4.2
Jeremias 4:4
He clearly brought out that the visible circumcision is a type of the invisible, and that if there is circumcision within, bodily circumcision is unnecessary. Taking a lead from this text, the divine apostle wrote to the Romans, "A person is not a Jew, you see, who is one outwardly, nor is circumcision what is outward, in the flesh; rather, a person is a Jew who is one inwardly, and circumcision is of the heart, in spirit and not in letter. That person's commendation comes not from people but from God." — ON JEREMIAH 1:4.4