Meurseult just goes through life without "feeling" anything, never showing any emotion. But ONCE he does. When the Chaplain talks to him. What does he shout at the chaplain, late in the book? Why is it significant?

The chaplain promises to pray and Meursault snaps, grabbing his collar and yelling. Meursault yells insults at the chaplain telling him not to waste his prayers. This is significant because his outburst at the Chaplain is the only time Meursault seems to show emotion about anything; he is passionate about his right to believe in nothing.