At the end of the first aliyah, the Torah tells us there was a famine in the land, and Yitzchak was tempted to go down to Egypt where his father, Avrohom, had gone in similar circumstances. But G-d told him not to leave the land of Israel because he was sanctified as an offering to G-d, by being brought to the akaida, and therefore not fit to leave the Holy Land of Israel. In this aliyah Yitzchak dwells near King Avimelech, and like his father Avrohom, his wife was thought to be his sister. King Avimelech notices that Rivkah is not his sister and issued a decree that no one touch them. The Torah says that while in this place, Yitzchak harvested a hundred times what he planted because G-d blessed him.