From the early Church Fathers to now.
“Sanctify unto me every firstborn that openeth the womb among the children of Israel, as well of men as of beasts: for they are all mine.”
“For who is really holy but the Son of God? Who properly opened the womb but he who opened a closed one? But it is marriage which opens the womb in all cases. The Virgin's womb, therefore, was especially opened, because it was especially closed.”
“Therefore let us draw together from the divine Scriptures instances in which we find "holy" used, and discover not only persons but also mute animals that are called "holy," and also find both "the vessels" of the ministry that are called "holy," and the garments which are said to be "holy," and even the places which were located in cities and suburbs and counted as priestly. Indeed, among the brute animals it is commanded through the law that "the firstborn" of calves or cattle be sacrificed to the Lord, and it says, You will not do any work with them because they have been consecrated to the Lord.”
“Males were sacred because they opened their mothers' wombs. They were offered before the altar of the Lord. Scripture says, "Every male that opens the womb.…" This phrase has a spiritual meaning. For you might say that "every male is brought forth from the womb" but does not open the womb of his mother in the way that the Lord Jesus did. In the case of every other woman, it is not the birth of an infant but intercourse with a man that opens the womb. But the womb of the Lord's mother was opened at the time when her offspring was brought forth, because before the birth of Christ a male did not even touch her womb, holy as it was and deserving of all respect.”
The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.