Toledot

This is the story of Isaac, son of Abraham. Abraham begot Isaac.

אברהם הוליד את יצחק ABRAHAM BEGAT ISAAC — Just because Scripture wrote, “Isaac, son of Abraham” it felt compelled to say “Abraham begat Isaac”, because the cynics of that time said, “Sarah became with child of Abimelech. See how many years she lived with Abraham without becoming with child”. What did the Holy One, blessed be He, do? He shaped Isaac’s facial features exactly similar to those of Abraham’s, so that everyone had to admit that Abraham begat Isaac. This is what is stated here: that Isaac was the son of Abraham, for there is evidence that Abraham begat Isaac (Midrash Tanchuma, Toldot 1).

But the children struggled in her womb, and she said, “If so, why do I exist?” She went to inquire of יהוה,

ויתרצצו AND [THE CHILDREN] STRUGGLED — You must admit that this verse calls for a Midrashic interpretation since it leaves unexplained what this struggling was about and it states that she exclaimed “If it be so, wherefore did I desire this” (i.e. she asked whether this was the normal course of child-bearing, feeling that something extraordinary was happening). Our Rabbis explain that the word ויתרוצצו has the meaning of running, moving quickly: whenever she passed by the doors of the Torah (i. e. the Schools of Shem and Eber) Jacob moved convulsively in his efforts to come to birth, but whenever she passed by the gate of a pagan temple Esau moved convulsively in his efforts to come to birth (Genesis Rabbah 63:6). Another explanation is: they struggled with one another and quarrelled as to how they should divide the two worlds as their inheritance (Yalkut Shimoni on Torah 111:2).

(24) When her time to give birth was at hand, there were twins in her womb.

והנה תומם BEHOLD, THERE WERE TWINS — The word for twins is written defective (without א and י) whilst in the case of Tamar it is written תאומים (with א and י); because in the latter case both children proved righteous whilst here one was righteous and the other wicked (Genesis Rabbah 63:8).

Then his brother emerged, holding on to the heel of Esau; so they named him Jacob. Isaac was sixty years old when they were born.

ואחרי כן יצא אחיו וגו AND AFTERWARDS HIS BROTHER CAME OUT, ETC. — I have heard a homiletical midrash that expounds it according to its simple meaning: It was with justice that he was grabbing him to hold him back. Jacob was conceived from the first drop and Esau from the second. Go and learn from a tube with a narrow opening - put in it two stones, one after the other. The one that goes in first will come out last, and the one that goes in last will come out first. It comes out that Esau, who was conceived last, came out first, and Jacob, who was conceived first, came out last. And [so] Jacob came to hold him back, so that the first for birth would be the same as the first for conception; and he would open [his mother's] womb and take the first-born status with justice (see Genesis Rabbah 63:8).