Ishodad of Merv : By mocking those who make the idols, [Isaiah] says, "The craftsman encourages the goldsmith, who strikes with the hammer." That is, even though they know that their hands have made them and that "they fasten them with nails," they are not ashamed to adore them. — COMMENTARY ON Isaiah 41:7 Theodoret of Cyrus : Look, [Isaiah] says, what the newcomers to the truth say to those who are still held prisoner to the error of idols, to show them their impotence: idols can neither walk nor hold themselves up without being fastened with nails. As for the phrase "it is a piece well joined," the three interpreters have rendered it, "it is a joint well made"; that is to say, the joints are well fitted. It has been put together by craftsmanship. — COMMENTARY ON Isaiah 12:41.7