And Isaac entreated the LORD for his wife, because she was barren: and the LORD was entreated of him, and Rebekah his wife conceived.
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Thus Isaac, the son of the promise, who as a figure of our Redeemer became obedient to his father even unto death, was born of parents who were old. He had a mother who had long been barren. Thus Jacob, the patriarch Joseph, Samson, [who was] the bravest of the chieftains, and Samuel, [who was] the most distinguished of the prophets, [all] had as their progenitors [mothers who were] for a long time barren in body but always fruitful in virtues. In this way their dignity would be known from the miraculous nativity of those who were born, and it might be proven that they would be famous in their lives, since at the very outset of their lives they transcended the norms of the human condition.