Deuteronomy 15:12
"If your brother, a Hebrew man or a Hebrew woman, is sold to you, he shall serve you six years, and in the seventh year you shall let him go free from you.
Jeremiah 34:14
'At the end of seven years each of you must set free the fellow Hebrew who has been sold to you and has served you six years; you must set him free from your service.' But your fathers did not listen to me or incline their ears to me.
Leviticus 25:39-41
"If your brother becomes poor beside you and sells himself to you, you shall not make him serve as a slave:
Exodus 21:2-6
When you buy a Hebrew slave, he shall serve six years, and in the seventh he shall go out free, for nothing.
Deuteronomy 15:1
"At the end of every seven years you shall grant a release.
John 8:35-36
The slave does not remain in the house forever; the son remains forever.