I gave a shiur last night on Zoom and Facebook Live. (Also uploaded
to YouTube, etc...)
The topic was the three mitzvos massiyos connected to Shavuos in
parashas Emor. Yes, there is an esrog, sukkah or matzah like mitzvah
in the parashah's description of Shavuos. These are also the 3 of the 4
mitzvos Chazal say MUST be taught to a prospective geir, singled out in
instructions to give a general survey. (And the fourth is related.) And
repeated in the Rambam. And probably underlies Megilas Rus's association
with Matan Torah.
Hint: NOT Shabbos, Kashrus and Taharas haMishpachah
Giveaway, if you bought the book: The shiur covers ideas I had since writing
Widen Your Tent sec. 7.10.
I left a video, audio, and the slideshow (PDF) online at
https://www.aishdas.org/asp/3-central-mitzvos-shiur
:-)BBii!
-Micha