Why does the Torah not write, 'va'Yimle'u Yamehah la'Ledes' (as it did in Bereishis 25:24, in connection with Rivkah)?
Rashi: Refer to 25:24:3:1.
Why does it spell "Te'omim" here with an 'Alef,' but regarding Rivkah (Bereishis 25:24) without an 'Alef'?
Rashi: Refer to 25:24:2:1.
Why does the Torah insert the (otherwise superfluous) word "b'Vitnah"?
Seforno: Because when they were still in the womb, people (Ha'amek Davar - the midwife) could tell that they were twins. This explains why the midwife tied the red thread around the first one's hand.
QUESTIONS ON RASHI
Rashi writes: "The word 'Te'omim' is written in full (Malei); but elsewhere it is written deficient, 'Tomim' (25:24) ... In this case, both of the twins would be righteous." But what is the derivation; isn't "Te'omim" normally written with an Alef?
Gur Aryeh: The word "Te'omim" in our verse is written not only with an Alef, but in full with a Vav. This is what hints that both were righteous. The word "Tomim" (25:24) in Toldos is written missing even the Alef, to hint that one of the twins would be wicked. 1
Also refer to 25:24:2:1*.
