Комментарий к Берешит 25:26

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).

ויקרא שמו יעקב. The word means he will remain at the heel, and the tail-end. This is based on the future mode of the word יעקב. Our sages (quoted by Rashi) say that the subject in our verse is G’d Who named Esau’s brother Yaakov, the reason for the unusual formulation being that after the destruction of the Kingdom of Edom and other nations, successor of Esau, only Yaakov and his descendants will remain. Our sages base all this on Jeremiah 46,28 אעשה כלה בכל הגויים...ואותך לא אעשה כלה, “I will make an end of all nations…but I will not make an end of you.”

ויקרא שמו יעקב. He called his name Jacob. The Torah refers to G'd, not to Isaac. Proof is that had Isaac been the subject in our verse, the Torah would not have continued : "and Isaac was sixty years, etc," but would have written: "and he was sixty years, etc."