Deuteronomy 15:19

19 All the firstborn males that are born of your herd and of your flock you shall sanctify to Yahweh your God: you shall do no work with the firstborn of your herd, nor shear the firstborn of your flock.

Deuteronomy 15:19 In-Context

17 then you shall take an awl, and thrust it through his ear to the door, and he shall be your servant forever. Also to your maid-servant you shall do likewise.
18 It shall not seem hard to you, when you let him go free from you; for to the double of the hire of a hireling has he served you six years: and Yahweh your God will bless you in all that you do.
19 All the firstborn males that are born of your herd and of your flock you shall sanctify to Yahweh your God: you shall do no work with the firstborn of your herd, nor shear the firstborn of your flock.
20 You shall eat it before Yahweh your God year by year in the place which Yahweh shall choose, you and your household.
21 If it have any blemish, [as if it be] lame or blind, any ill blemish whatever, you shall not sacrifice it to Yahweh your God.
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