Exodus 21:2-6

2“When you buy a Hebrew slave, he is to serve for six years; then in the seventh he is to leave as a free man without paying anything.

3If he arrives alone, he is to leave alone; if he arrives with a wife, his wife is to leave with him.

4If his master gives him a wife and she bears him sons or daughters, the wife and her children belong to her master, and the man must leave alone.

5“But if the slave declares, ‘I love my master, my wife, and my children; I do not want to leave as a free man,’

6his master is to bring him to the judges and then bring him to the door or doorpost. His master will pierce his ear with an awl, and he will serve his master for life.