Genesis 25:19

And these are the generations of Isaac, Abraham’s son: Abraham begat Isaac:

These are the generations of Isaac, opening the record of his descendants and family line. The formula names Isaac as Abraham's son, marking the continuation of Abraham's family story and the next link in that family. Through that link the promised Seed was to come, with the promises given to Abraham extending to Isaac and then from Isaac to Jacob.

The chapter to which it belongs is a chapter of genealogies, recounting Abraham's death, the probable last meeting of Isaac and Ishmael, and a forecast of the characters of Esau and Jacob. It stands within the account of God's providential dealings with Abraham's family, identifying Abraham as the chosen ancestor of the promised Seed. It also shows God working for Isaac when he did not contend for his rights but committed his cause to God.

From this introduction comes the birth of Rebekah's twin sons, Esau and Jacob, born when Isaac was sixty, fifteen years before Abraham died. Their names mean red and supplanter, respectively. In this family setting Jacob is Isaac's younger son, who takes advantage of Esau's hunger to obtain Esau's birthright and later obtains the blessing intended for his brother by fraud. That history leads on to Jacob's eventual victory, in which he became Israel, a prevailer with God.