The Rav said that only the Am Yisroel are the “banim” of Hashem. But doesn’t the posuk of “b’ni bichori Yisroel,” imply that while we are His bechor, but that the other nations are also considered His children?
Look, he’s asking a good question. Nothing wrong with a little lomdus. If it says, “b’ni bichori Yisroel,” that they are my firstborn, that implies that the rest of the nations are not “bechorim,” but they’re at least “banim.” The answer is – No! Am Yisroel are “banim” and nobody else is “banim.” But not only are they “banim,” but they’re beloved like “b’ni bichori.” That’s what it means.
“Banim atem la’shem Elokeichem.” It doesn’t say, “bechorim atem la’shem Elokeichem.” Banim atem! Atem! Only you are “banim” to me. Nobody else. Only that, not only are you “banim,” but you are beloved to me like a bechor. Because a bechor is especially beloved. That’s all that it means.