“I will bless her, and I will also give you a son from her; I will bless her, and she shall become nations; kings of peoples will be from her” (Genesis 17:16). “I will bless her, and I will also give you a son from her; [I will bless her…]”6The verse indicates that God gave her two blessings. – Rabbi Yehuda and Rabbi Neḥemya, Rabbi Yehuda says: I will bless her by giving her a son, and I will bless her with the blessing of milk.7The blessing was that despite her old age she would be able to nurse her son.
Rabbi Neḥemya said to him: Was she already given tidings regarding milk? Why, she was not even pregnant yet. Rather, it teaches that the Holy One blessed be He restored her body to the days of her youth. Rabbi Abahu in the name of Rabbi Yosei bar Ḥanina: [God said:] ‘I will impose fear of her over all the idolaters so that they will not torment her and call her the barren woman.’
Rabbi Yudan in the name of Reish Lakish: She did not even have a womb, and the Holy One blessed be He now carved out a womb for her. “Kings of peoples will be from her” – Rabbi Ḥama ben Rabbi Ḥanina said: From here Abraham expounded when he remarried Ketura.8The midrash identifies Ketura as Hagar. Sarah had said that she regarded Hagar’s children as her own (Genesis 16:2). This verse foretells that Sarah would become the forebear of “Kings of peoples,” and it was to fulfill this prophecy that Abraham remarried Ketura-Hagar and fathered six children from her (Genesis 25:1–2).