MeAm Lo'ez on Yeshayahu 41:4

Why did G-d do that for Avraham?  Because He "called from the beginning" - He knew Avraham's righteous offspring of the future.  Why did G-d empower Avraham over the four mighty kings who captured Lot?  To symbolize his descendants' four exiles, reassuring him that as He was the "First" to be with him, He would the "last of his exiled descendants.  As He roused Avraham to leave his native Kasdim for Kenaan, would He rouse future generations to leave the exile for the Promised Land.