I have two questions that perhaps you could help me with. I searched for answers to no avail.
1) B"B 147a Tosfot d.h. Minayin: the Gemara only intended to bring Scriptural support as "Asmachta b'alma", despite a discussion of what else those verses could have meant.
Does this not contradict Tosfot's conclusion in Succah 9a that a Succah is prohibited M'D'Oryta, since the Gemara discusses alternative derivations from the verses, it cannot be Asmachta B'Alma?
2) B"B 147b Rashbam D.h. Matnas. Rashbam, in explaining that Matnas Schiv Meira is only Rabbinic, takes the trouble of explaining the verses brought earlier, that seem to support the idea that it is M'D'Oryta, where Chizkiyahu and Achitofel leave final instructions for their households upon their death.
I do not understand why these verses contradict Rava's position, that Matnas Shiv Meira is only Rabbinic. Could not have the Rabbinic decree already been instituted as early as the days of King David (such as e.g. Muktza was in place already)?
Thanks for your help,
(1) This question is asked by the Yad Malachi (rule 19) and the Maharsham (6:134:2 DH v'Ulam and 9:98:1 DH Aval). Unfotunately, neither of them give an answer. It sounds from the Maharsham that he believed that the Tosfos argue with one another.
(2) I have not found anyone who asks this question, but I can suggest that perhaps any decree made so early would have been well known and it is unlikely that there would be a dispute about it.