"There were a lot of clouds," his uncle said, and continued to look straight before him "but they were blowing fast, so there was a lot of sunshine too. Right when they began to lower your father into the ground, into his grave, a cloud came over and there was a shadow just like iron, and a perfectly magnificent butterfly settled on the-coffin, just rested there, right over the breast, and stayed there, just barely making his wings breathe, like a heart." Andrew stopped and for the first time looked at Rufus. His eyes were desperate.
This passage is taken from Chapter 20, the last chapter in the novel. Andrew is describing to Rufus the butterfly he saw at Jay's funeral. He begins by saying that if anything could make him believe in God, it would be that butterfly. After the butterfly landed, it stayed on the coffin all the way into the ground before flying away. The butterfly is a symbol of hope; Andrew wrestles with his idea that the butterfly also represents some sort of divine influence that he cannot quite bring himself to accept.