Exodus 13:13
11 “When the Lord brings you into the land of the Canaanites, as he swore to you and to your fathers, and gives it to you, 12 then you must give over to the Lord the first offspring of every womb. Every firstling of a beast that you have—the males will be the Lord’s. 13 Every firstling of a donkey you must redeem with a lamb, and if you do not redeem it, then you must break its neck. Every firstborn of your sons you must redeem. 14 “In the future, when your son asks you ‘What is this?’ you are to tell him, ‘With a mighty hand the Lord brought us out from Egypt, from the land of slavery. 15 When Pharaoh stubbornly refused to release us, the Lord killed all the firstborn in the land of Egypt, from the firstborn of people to the firstborn of animals. That is why I am sacrificing to the Lord the first male offspring of every womb, but all my firstborn sons I redeem.’
Numbers 18:15
13 And whatever first ripe fruit in their land they bring to the Lord will be yours; everyone who is ceremonially clean in your household may eat of it. 14 “Everything devoted in Israel will be yours. 15 The firstborn of every womb which they present to the Lord, whether human or animal, will be yours. Nevertheless, the firstborn sons you must redeem, and the firstborn males of unclean animals you must redeem. 16 And those that must be redeemed you are to redeem when they are a month old, according to your estimation, for five shekels of silver according to the sanctuary shekel (which is 20 gerahs). 17 But you must not redeem the firstborn of a cow or a sheep or a goat; they are holy. You must splash their blood on the altar and burn their fat for an offering made by fire for a pleasing aroma to the Lord.
Notes and References
"... (Exodus 13:11) ... This attempted clarification in the passage leaves more questions than it answers. One question is whether this passage really includes girl-children as I insist. There is a long-standing practice in Judaism of “redemption of the firstborn son,” based in part on this verse and its subsequent interpretive history. In order to read Exodus 13:13 as pertaining only to males as do NRSV, JPS, GSJPS, and Fox, one has to disregard the use of kol (“all,” “each,” and/or “every”) in verses 1 and 12, and one has to translate kol bekor adam as “every firstborn male” rather than as “every firstborn human-person.” This is a long-standing traditional Jewish interpretation, based in part on seeing parallelism between hazakariym, “the males,” applied to animals in verses 12 and 15 and adam, “human,” in the latter portion of verse 15 ... Numbers 18:15 will eventually specify five shekels as the means for human redemption. Exodus as a literary unit remains mysteriously silent on the matter. It may be that the ransom ritual and requirements were so well known that there was no need to record them in the text. The text is also silent on whether firstborn status brings with it any religious or cultural status, apart from the general practice of birth-order hierarchy and decided preference for and bias toward males ..."
Gafney, Wilda Womanist Midrash: A Reintroduction to the Women of the Torah and the Throne (pp. 102-103) Westminster John Knox Press, 2017