Whereas Abraham was primarily a wanderer, a herdsman of sheep and camels and the like, Isaac tried to remain more or less in one place.
His passivity, the "fear" of Isaac, which began at the time of his being bound for the sacrifice, was the mood of his life.
It was the sign of his instrumentality.
He was the trial.
Isaac had to remain bound forever on the altar, the one to whom things were done because that was the entire field of his creativity.
He was the background for a nation, the ground for a new reality.
–Rabbi Adin Steinsaltz
From Biblical Images by Rabbi Adin Steinsaltz