Another interpretation (of Genesis 12:1): GO FORTH. For your sake I created the world. Rabbi Tahalifa said: The Holy One, blessed be He, said: I looked upon you, and I created the world, as it is stated (in Genesis 2:4): "These are the generations of the heavens and the earth when they were created (be-hibbar'am)." What is the meaning of "when they were created (be-hibbar'am)"? Through Abraham (be-Avraham) He created them.
For Abraham's Sake God Created the World in Lech Lecha
Midrash Tanchuma Buber, Lech Lecha 4:5
ד"א לך לך בשבילך בראתי את העולם, אמר ר' תחליפא אמר הקב"ה בך הבטתי ובראתי את העולם, שנאמר אלה תולדות השמים והארץ בהבראם (בראשית ב ד), מהו בהבראם, באברהם בראם.