The firstborn of an unclean animal had to be redeemed by an estimation of the priest, with the addition of one-fifth (Lev 27:27; Num 18:15). According to Exod. 13:13; 34:20, the firstborn of an ass was either ransomed by a sheep or lamb, or its neck had to be broken.

Figuratively, Israel was God’s “firstborn” (Exod 4:22; Jer 31:9) and enjoyed priority status. God compared His relationship to Israel with the relationship of a father and his firstborn son. Within Israel, the tribe of Levi represented the firstborn of the nation in its worship ceremony (Num 3:40-41; 8:18).