Who is "Re'acha v'Re'a Avicha"?
Rashi: It is Hashem, who is called Re'a to Yisrael 1 . He is Re'a Avicha, for He endeared your fathers.
Malbim: It is a friend whose love was tested. He was always your friend and your father's friend.
Rashi 25:17: Hashem is called Re'a (friend) to Yisrael - "Zeh Dodi v'Zeh Re'i" (Shir ha'Shirim 5:16).
Why does it say "Al Ta'azov"?
Rashi: If you abandon, punishments will come upon you.
Malbim: Even though nature puts love between brothers, his love is only when it is good for you and you do not need him. On the day of your calamity, his love will cease, either because "Kol Achei Rash Sene'uhu" (19:7), or because he does not want to help you.
What is "Beis Achicha"?
Rashi: Do not rely on Bnei Esav and Yishmael, that they will draw you close. When Yisrael were exiled to Bavel, they asked their captors 'bring us via the way of Bnei Esav and Yishmael. They gave to them salted food and inflated pouches. (Yisrael opened them in order to drink; the compressed air entered their innards, and killed them - Eichah Rabah 2:4).
Which close neighbor is better than a distant brother?
Rashi: It is better that the One who is "close to those who call to Him" (Tehilim 145:20) dwells among you, than for you to come to a brother who distanced, saying "Yikrevu Yemei Evel Avi [and I will kill Yakov]" (Bereishis 27:41).
Malbim: One who is close to you because he constantly dwells by you, is better than someone distant, even if [the latter] is your brother.
