רבינו בחיי — ויבא אברהם לספד לשרה ולבכותה

Q — Why is Yitzchak entirely absent from his mother's eulogy and burial — and indeed from the entire scene of the akeida's aftermath? The pasuk says "וישב אברהם אל נעריו" in the singular, not "וישובו אל הנערים."

A — Rabbeinu Bachya: Sarah's death was caused by hearing the news of the akeida, with Yitzchak as its unwitting cause; they could not bear to tell him she had died. But more than that, he was not anywhere to be found: Yitzchak remained on Har HaMoriah for three years after the akeida, completing his fortieth year there. The Torah passes over him in silence until the verse "ויצחק בא מבוא באר לחי ראי" when he comes to meet Rivkah. The chiddush: the akeida did not end at the mizbeach. Yitzchak entered a hidden phase of three years on the mountain, in a state of dveykut, and his absence from the Torah's narrative during these years is itself the testimony that he was elsewhere — closer to the place of the akeida than to ordinary life.