Bible Verses About Servants: By birth

Which when Abram had heard, to wit, that his brother Lot was taken, he numbered of the servants born in his house, three hundred and eighteen, well appointed: and pursued them to Dan.

O LORD, truly I am thy servant; I am thy servant, and the son of thine handmaid: thou hast loosed my bonds.

Is Israel a bondman, or a homeborn slave? why then is he become a prey?