What happens between Rabbi Eliahou and his son? What does Wiesel’s reaction to this incident reveal about his relationship with God?

Elie witnesses the rabbi desperatly looking for his son during the prisoners' horrible march to Gleiwitz. The Rabbi insists that his son would never leave him. Elie had seen his son march ahead when his father stumbled in the march. The Rabbi's son had forsaken his father. Elie notes that he is capable of doing the same which bothers him. Elie's relationship with God is now strained. He no longer sees God in his world as he once did.