‏ Deuteronomy 15:19-20

19 aAll the firstborn males that are born of your herd and flock you shall dedicate to the Lord your God. You shall do no work with the firstborn of your herd, nor shear the firstborn of your flock. 20 bYou shall eat it, you and your household, before the Lord your God year by year at the place that the Lord will choose.
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