This means that they are selling their family members as slaves to their fellow Jews. The full meaning of this statement can be made clear. Alternate translation: "Now you are selling your own people to be slaves of your fellow Jews, so that they might later sell them back to us" (See: [[rc://en/ta/man/translate/figs-explicit]])
This can be stated in active form. Alternate translation: "who people had sold as slaves to the nations" (See: [[rc://en/ta/man/translate/figs-activepassive]])