Deuteronomy 15:12
If thy brother, an Hebrew, sell himself to thee, or an Hebrewess, he shall serve thee six years and the seventh year thou shalt let him go free from thee.
Jeremiah 34:14
'When seven years are out, every man shall let his bought servant, a Hebrew go free, if he have served him six years.' But your fathers obeyed me not and hearkened not unto me.
Leviticus 25:39-41
"'If thy brother that dwelleth by thee wax poor and sell himself unto thee, thou shalt not let him labour as a bondservant doeth:
Exodus 21:2-6
If thou buy a servant that is an Hebrew, sixth years he shall serve, and the seventh he shall go out free paying nothing.
Deuteronomy 15:1
At the end of seven years thou shalt make a free year.
John 8:35-36
And the servant abideth not in the house forever: But the son abideth ever.