The Sages provide a rationale for God’s commandment to Abraham to depart from Haran and to go to “the land that I will show you.” They also explain the particular difficulty that fulfilling this commandment entailed.

Rabbi Berekhya said: To what was Abraham our patriarch comparable? To a bottle of perfume that was sealed with a tight-fitting lid and placed in a corner. As long as it sat there its fragrance did not diffuse. Once it was moved, its fragrance diffused. So the Holy One, blessed be He, said to Abraham our patriarch: Move yourself from place to place, and your name will be exalted in the world. “To the land that I will show you” (Genesis 12:1). God did not say to him: To such and such place, telling him where to go. This wording of the command is an ordeal within an ordeal; is there a person who goes and does not know to which place he is going? What did Abraham do? He took his belongings and his wife. (Bereshit Rabba 38)