Exodus 21:1-4

“Now these are the ordinances which you are to set before them:

“If you buy a Hebrew slave, he shall serve for six years; but on the seventh he shall leave as a free man without a payment to you.

If he comes alone, he shall leave alone; if he is the husband of a wife, then his wife shall leave with him.

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