Exodus 21:6

21:6 then his master must bring him to the judges, and he will bring him to the door or the doorposts, and his master will pierce his ear with an awl, and he shall serve him forever.

Exodus 38:30

38:30 With it he made the bases for the door of the tent of meeting, the bronze altar, the bronze grating for it, and all the utensils of the altar,