When Avraham went to do the Akeidah, the Yetzer Hara tried to convince him he'd misunderstood what Hashem wanted. To some of the challenges, Avraham and Yitzchak said Al Minas Kein, we will do it regardless. Why did they respond that way, instead of defending their position? The Rosh Yeshiva's famous Shmuess in how to best fight those nagging doubts.