Venue: YU Torah MiTzion Beit Midrash Zichron Dov YU Torah MiTzion Beit Midrash Zichron Dov

Gemara:

Beitza 

Collections: Rabbi Torczyner Beitza 2014

References: Beitza: 4b  

Description

Nullifying wood that falls into an oven on Yom Tov. The rule of אין מבטלין איסור לכתחילה, and an exception permitting nullification of items that are only prohibited rabbinically, under certain conditions (only true d'rabbanans, and issurei achilah rather than issurei hanaah)