TSK · Numbers 18:15

“Set apart to me every firstborn male– the first offspring of every womb among the Israelites, whether human or animal; it is mine.”

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.

“Do not hold back offerings from your granaries or your vats. You must give me the firstborn of your sons.

Redemption of the Firstborn“‘Surely no man may consecrate a firstborn that already belongs to the LORD as a firstborn among the animals; whether it is an ox or a sheep, it belongs to the LORD.

And for the redemption of the 273 firstborn males of the Israelites who exceed the number of the Levites,

The priests should receive the silver they need from the treasurers and repair any damage to the temple they discover.”