John Gill Bible Commentary

But unto the sons of the concubines which Abraham had,.... These were Hagar and Keturah, though they are both called his wives, Gen 16:3; yet they were concubines; so Keturah, Ch1 1:32; they were, as some render the word, "concubine wives" (e); they were half wives or secondary ones: the Jewish writers say that they were espoused, but not by writing, as wives were; they were under the lawful wife, when there were any, and a kind of head servants in the family, and their children did not inherit; now the sons of the concubines of Abraham were Ishmael by Hagar, and the six above mentioned by Keturah: to these Abraham gave gifts; money, gold and silver, of which he had plenty: the Targum of Jonathan calls them substance and movable goods; by this it appears, that though he had sent Ishmael away without anything, yet he afterwards remembered him, and gave him a portion with the rest of the children of his, concubines: and sent them away from Isaac his son; that they might not be troublesome to him and his family; and that there, might be no contention among them about inheriting the land of Canaan given to him and his seed: and this Abraham did while he yet lived; or otherwise after his death a separation would not have been easily made; but his authority had weight with them: and they were sent by him eastward, into the east country; into Arabia, and the parts thereabout, which lay east from the place where Abraham was; these are the children of the east, mentioned along with the Midianites, who sprung from Keturah, Jdg 6:3. (e) "concubinarum uxorum", Junius & Tremellius, Piscator.