Deuteronomy 15:17-19 World English Bible (WEB)
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 female servant you shall do likewise. 18 It shall not seem hard to you when you let him go free from you, for he has been double the value of a hired hand as he served you six years. Yahweh your God will bless you in all that you do. 19 You shall dedicate all the firstborn males that are born of your herd and of your flock to Yahweh your God. You shall do no work with the firstborn of your herd, nor shear the firstborn of your flock.