Numbers 18:15 → Exodus 13:12

Exodus 13:12 commands Israel to "present to the LORD" (הַעֲבַרְתָּ, ha'avarta) "the firstborn male of every womb" (פֶּטֶר רֶחֶם, peter rechem), grounding this obligation in the Passover deliverance when God struck Egypt's firstborn but spared Israel's. Numbers 18:15 assigns the administration of this law to the priesthood: "the firstborn of every womb... belongs to you. But you must surely redeem every firstborn son." Numbers adds the specific redemption price (five shekels at one month old, v. 16) that Exodus left unspecified, and assigns the revenue to the priestly support system. The connection shows how Pentateuchal legislation develops: Exodus establishes the theological principle (firstborn belong to God because of Passover), Numbers institutionalizes it within the priestly economy. The redemption itself is denoted by the specific verb פָּדָה (padah, "to redeem"), underscoring that Numbers institutes a substitutionary payment rather than a mere administrative transfer.