The aggada cited on Yoma 28B says Avraham kept all mitzvos and evem made an Eruv Tavshilin, however it does not agree with the midrash recorded in Bereishis Rabah 64:6. Yoma says Avraham kept eruv tavshilin; the midrash says eruv chatzaros.
Meanwhile the Vilna Gaon (Kol Eliyahu #26) says our gemrah is wrong, and that actually it was Eruv Techumin. Additionally, the Malbim says "Eruv Tavshilim" means the patriarchs kept their milk and meat separate, and not that they performed the rabbinic ritual that allowed them to prepare for shabbos on Yom Tov.
So, are we starting to see why its an act of violence against both Rashi and the tradition to teach simply that "Rashi says Yaakov kept all 613 mitzvos including Eruv Tavshilim"
Yet this bowdlerized travesty of Rashi's position is precisely what's taught, and in some circles you're a kofer for disagreeing, and even for saying that as a non-kohen keeping "all mitzos" was impossible for Yaakov ("Impossible? How can you say anything was impossible for Yaakov?")
It is this reprehensible state of affairs, this sad way of thinking, that Rabbi Yair Hoffman seems to want continued in the name of "tradition".
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