PRIMOGENITO. — Every male who was the first offspring (Heb. bēkhār, synonymous with pēter rēhem, rendered exactly in the Vulgate as «qui aperit vulvam»), whether human or animal, was sacred to the Lord under the Mosaic Law (Ex. 13, 2. 12. 15; 22, 29 f.; 34, 19 f.). This consecration was linked to the destruction of the Egyptian firstborn (ibid. 13, 14 f.; Num. 3, 13; 8, 17).
Exodus contemplates the possibility of redeeming the firstborn of the donkey by sacrificing a lamb (Ex. 13, 12 f.; 34, 20). Leviticus (27, 27) prescribes the redemption of every unclean animal according to the priest’s valuation; the price is assigned to the sanctuary. In Num. 18, 15-19 Yahweh transfers all his rights over the firstborn to the priests, to whom they belong in their entirety; this seems to be an adaptation subsequent even to Deut. 15, 19-23, where the flesh of the firstborn offered in a peace offering was consumed, in the portion due to them, by the offerers themselves. Deuteronomy (ibid.) adapts the legislation of the desert to Israel’s new condition in Canaan. Thus, whereas in Ex. 22, 29 the slaughter of the firstborn was prescribed for the eighth day after birth, in Deuteronomy it had to take place during the first year, for example, on the occasion of a pilgrimage to the one sanctuary. Since they were sacred to Yahweh, the firstborn could not in the meantime be used for field work or subjected to shearing. The miñnic treatise Bēkhōrōth offers Jewish interpretations and determinations concerning this law.
For human firstborn Yahweh established redemption (Ex. 13, 13; 34, 20), fixed at 5 silver shekels (Num. 3, 47; 18, 15 f.); the substitution of the Levites, at the time of their establishment, took the place of the redemption of an equal number of Israelite firstborn (Num. 3, 11 ff. 41-51). On this occasion, the Lord assigned the sum of the redemption to the priests, who, together with the Levites, were exempt from this law. The firstborn of animals were to be sacrificed to Yahweh if clean, and killed if unclean.
There is no obligation in the Tōrāh to present the male firstborn in the Temple for redemption; this custom prevailed after the exile (Neh. 10, 36), and advantage was taken of the visit which the mother had to make to the Temple (Lev. 12, 2-8) for the other law concerning purification. The Most Holy Virgin conformed to the pious custom then in force (Lc. 2, 22). The Jews remained faithful to the prescription concerning the redemption of the firstborn even after the destruction of the Temple. On the 31st day after the birth, the parents invited a priest to the banquet and gave him the 5 shekels. Jesus is called Mary’s firstborn (ibid. 2, 7) according to Jewish usage, which takes no account whatsoever of the birth of other children (cf. s. Girolamo, Contra Helvidium, 101); this is confirmed by the use of πρωτότονος in the inscription found in 1922 near Tell el-Jebudijjah in Egypt. In polygamy there could be several firstborn; the firstborn, in relation to the father, «primizia della sua forza» (Gen. 49, 3; Deut. 21, 17), held a privileged position over his brothers in ancient families; he inherited a double portion and his father’s position as head of the clan—a privilege that could be lost (Esau, Ruben) or transferred by the father to another son (Deut. 21, 15 ff.). For this right (Heb. bēkhōrōth) cf. Gen. 25, 31-34; 27, 36; 43, 33, etc.; Hebr. 12, 16: τὰ πρωτοτόκια. The firstborn were the objects of the greatest affection (cf. Gen. 22, 2. 12. 16; Ios. 6, 26; II Reg. 3, 27; Zach. 12, 10). God therefore calls Israel «suo p.» (Ex. 4, 22 f.; Eccli. 36, 14; cf. Ier. 31, 9). And «figlio prediletto» (Lc. 20, 13: ἀγαπητός) is equivalent to only son (Mc. 12, 6: cf. M.-J. Lagrange, Ev. selon st Luc, 3ª ed., Parigi 1927, p. 509).