לרפואת הרב אלכסנדר ישראל בן חיה מרתא בתוך שח"י
Yitzchak's middah was gevurah. This is also the middah we are supposed to work on in the second week of sefirah. The goal is to reach the level in one's avoda to reveal that all of the pains and hardships are revealed to be only for the good. This is through a complete avoda of constantly overcoming [להתגבר] the evil and suppressing it [כפייתו על פניו] and thereby the hiddeness [הסתר] is nullified and its good albeit hidden purpose is revealed.
In this context it is revealed that the most difficult troubles with Eisav and Amalek also bring to a higher and more positive purpose to the extent that the head of Eisav rolls into מערת המכפלה to the lap of Yitzchak [as the Zohar revealed], meaning that from the perspective of the head and thought even the worst tragedies and troubles bring to a revelation of Hashem and His goodness.
According to this we can understand that when Yitzchak steps up to defend the Jewish people at the end of days [see Shabbos 89], his job is to show that there is a positive root even to weakness and sin just like the sweet smelling ktores that includes foul smelling chelbinah.
From here is the root of chizzuk when we say the bracha of "אתה גבור" which is the bracha of Yitzchak [the first bracha of שמונה עשרה corresponds to Avraham and the third to Yaakov] who holds on to the גבורה of what the Gemara says "לעולם יגביר אדם יצר הטוב על יצר הרע" - one should always strengthen the יצר הטוב over the יצר הרע, through which the harsh covering of evil is weakened and positive purpose is revealed.
[עפ"י "ואני תפילה" עמ' כ"ט-ל]
