Deuteronomy 15:12
If thy brother, a Hebrew man, or a Hebrew woman, have been sold unto thee, he shall serve thee six years, and in the seventh year thou shalt let him go free from thee.
Jeremiah 34:14
At the end of seven years ye shall let go every man his brother, a Hebrew, who hath sold himself unto thee; when he hath served thee six years, thou shalt let him go free from thee. But your fathers hearkened not unto me, neither inclined their ear.
Leviticus 25:39-41
And if thy brother grow poor beside thee, and be sold unto thee, thou shalt not compel him to serve as a bondservant:
Exodus 21:2-6
If thou buy a Hebrew bondman, six years shall he serve; and in the seventh he shall go out free for nothing.
Deuteronomy 15:1
At the end of seven years thou shalt make a release,
John 8:35-36
Now the bondman abides not in the house for ever: the son abides for ever.