She shall crush. Ipsa, the woman: so divers of the fathers read this place, conformably to the Latin: others read it ipsum, viz. the seed. The sense is the same: for it is by her seed, Jesus Christ, that the woman crushes the serpent’s head. (Challoner)

The Hebrew text, as Bellarmine observes, is ambiguous: He mentions one copy which had ipsa instead of ipsum; and so it is even printed in the Hebrew interlineary edition, 1572, by Plantin, under the inspection of Boderianus. Whether the Jewish editions ought to have more weight with Christians, or whether all the other manuscripts conspire against this reading, let others inquire. The fathers who have cited the old Italic version, taken from the Septuagint agree with the Vulgate, which is followed by almost all the Latins; and hence we may argue with probability, that the Septuagint and the Hebrew formerly acknowledged ipsa, which now moves the indignation of Protestants so much, as if we intended by it to give any divine honour to the blessed Virgin Mary. We believe, however, with St. Epiphanius, that “it is no less criminal to vilify the holy Virgin, than to glorify her above measure.” We know that all the power of the mother of God is derived from the merits of her Son. We are no otherwise concerned about the retaining of ipsa, she, in this place, than in as much as we have yet no certain reason to suspect its being genuine. As some words have been corrected in the Vulgate since the Council of Trent by Pope Sixtus V. and others, by Pope Clement VIII. so, if, upon stricter search, it be found that it, and not she, is the true reading, we shall not hesitate to admit the correction: but we must wait in the mean time respectfully, till our superiors determine. (Haydock) Kemnitzius certainly advanced a step too far, when he said that all the ancient fathers read ipsum. Victor, Avitus, St. Augustine, St. Gregory, &c. mentioned in the Douay Bible, will convict him of falsehood. Christ crushed the serpent’s head by his death, suffering himself to be wounded in the heel. His blessed mother crushed him likewise, by her co-operation in the mystery of the Incarnation; and by rejecting, with horror, the very first suggestions of the enemy, to commit even the smallest sin. (St. Bernard, ser. 2, on Missus est.) “We crush,” says St. Gregory, Mor. 1. 38, “the serpent’s head, when we extirpate from our heart the beginnings of temptation, and then he lays snares for our heel, because he opposes the end of a good action with greater craft and power.” The serpent may hiss and threaten; he cannot hurt, if we resist him. (Haydock)