Avraham Avinu returned home – with his two aides – but where was Yitzchak Avinu? Four people left for the mountain; three returned home. Yitzchak must have taken a different route. The Midrash Rabbah explains that Yitzchak took a detour to study Torah in the yeshivah of Shem (son of Noach). Targum Yonasan adds that Yitzchak studied there for three years, until he met Rivkah Imeinu. Was something wrong with Avraham’s yeshivah? It seems to have sufficed for thirty-seven years. Why did he change? Certainly Shem was not a better rebbe than Avraham.
Horav Moshe Neriyah, zl, quotes the Rambam, who describes Avraham’s methodology of teaching the masses. As opposed to that of Shem, who secluded himself in a corner and taught only the yechidei segulah, special students, cherished few, whose acumen, desire and spiritual plateau were all on a level far above the average student, Avraham believed in outreach: every person must be taught that there was a Creator, Who was the G-d of Creation and the G-d of history. It was this approach to Torah which he infused in Yitzchak – up until they left for Har HaMoriah, for (literally) what was to be the seminal experience of a lifetime. On Har HaMoriah, Yitzchak evinced such an unparalleled display of faith in the Almighty that he could no longer have him return to his original environment. He was now on such a sublime spiritual plane that he had to be secluded away from everyone. Yitzchak would carry on Avraham’s legacy, to reach out to those who were unaffiliated, but it could no longer be a project in which he would circulate among the masses and be exposed to all sorts of individuals, some of whom would detract from his unique spiritual plateau.
Thus, he was compelled to “switch yeshivos” to alter his focus from ahavah, love, and chesed, kindness, which personified Avraham’s home and service to Hashem, to a yeshivah where the primary focus was on yiraah, fear/awe, in order to nurture the pachad Yitzchak, fear of Yitzchak. Pachad Yitzchak was the middah, character trait, which best described our second Patriarch.
When Yitzchak met Rivkah, he was coming directly from three years of non-stop learning with no exposure to society. This learning experience came on the heels of an Akeidah, Binding of Yitzchak, which set the tone and standard for his ultimate devotion to Hashem. This is how Yitzchak began his married life. Is it any wonder that what concerned him most in seeking a wife was replacing his mother, filling the spiritual void left by her passing?