"And there was an argument between the herdsmen of Abram's livestock and the herdsmen of Lot's livestock, and the Canaanite and the Perizite were then in the land" (Breisheet 13:7).
“G-d said to Avram, go away from your county, your birthplace and your father’s home, to the land that I will show you” (Breisheet 12:1). While it is self-evident that Avraham would take his wife with him, it is not at all obvious that his nephew Lot would or should accompany him. Perhaps it was precisely his family—parents, sibling, cousins, nieces and nephews— that he must leave behind in order to establish a great nation in a faraway land.
The Divine choosing of Avraham marks the beginning of Jewish peoplehood. Tellingly, this relationship begins with G-d's command (obeying G-d's commands is the primary function we have) lech lecha,"go for you from your land, your birthplace, and from your father's home" (12:1). We are told little of Avraham's journey to Israel, though one can only imagine how difficult it must have been, physically, emotionally, and psychologically.
“And G-d said to Abram, ‘Go forth from your land, your birthplace and the land of your fathers’”. With nary a word, Abram picks himself up and, along with his wife and nephew, departs for an unknown land. Yet his stay there is short, as soon afterwards famine ensues and Abram descends to the land of Egypt.
Was this a prudent move to feed his family, realizing—as he did—that one may not rely on miracles? Or did Abram demonstrate a lack of faith in G-d, who had promised Abram that in his new land he would become the leader of a great nation?