*Minor differences ignored. Grouped by changes, with first version listed as example.
The two sons of Isaac. Isaac has been already mentioned as a son of Abram, along with Ishmael, in 1-Chronicles 1:28. But here the continuation of the genealogy of Abraham is prefaced by the remark that Abraham begat Isaac, just as in Genesis 25:19, where the begetting of Isaac the son of Abraham is introduced with the same remark. Hence the supposition that the registers of the posterity of Abraham by Hagar and Keturah (1-Chronicles 1:28-33) have been derived from Genesis 25, already in itself so probable, becomes a certainty.
*More commentary available at chapter level.