Deuteronomy 15:19

19 Every firstling male born of your herd and flock you shall consecrate to the Lord your God; you shall not do work with your firstling ox nor shear the firstling of your flock.

Deuteronomy 15:19 In-Context

17 then you shall take an awl and thrust it through his earlobe into the door, and he shall be your slave forever. You shall do the same with regard to your female slave.
18 Do not consider it a hardship when you send them out from you free persons, because for six years they have given you services worth the wages of hired laborers; and the Lord your God will bless you in all that you do.
19 Every firstling male born of your herd and flock you shall consecrate to the Lord your God; you shall not do work with your firstling ox nor shear the firstling of your flock.
20 You shall eat it, you together with your household, in the presence of the Lord your God year by year at the place that the Lord will choose.
21 But if it has any defect—any serious defect, such as lameness or blindness—you shall not sacrifice it to the Lord your God;
New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.