Tanach · Rishonim on Tanach · Ibn Ezra · Torah
Ibn Ezra on Deuteronomy 13:7/אבן עזרא על דברים י״ג:ז׳
אכי יסיתך אחיך. הטעם אפי' אחיך:
1IF THY BROTHER…ENTICE THEE. This means even thy brother.32 is to be understood as even if your brother entices you, for the law applies to anyone who entices you.
בוטעם בן אמך. שהייתם בבטן אחת והאם כגוף והאב כצורה והצורה לא יבינוה כי אם מתי מעט:
2The import of thy mother is, you33. This is an appellation rarely used in Scripture. The question thus arises, “Why did Scripture add the son of thy mother?” Furthermore, why did the Torah not describe the brother as the son of thy father? Hence I.E. comments that the matter from which a person is made comes from the mother; the father’s sperm (so I.E. believed) shapes the matter. Thus a person, biologically speaking, is closer to a brother from a mother than to a brother from a father, and probably has closer emotional ties to him. Hence Scripture states, even if your brother who is made of the same matter as you entices you, do not listen to him. were in one womb. The mother is like matter and the father is like form.34 not thy father. Very few people understand the nature of form.