What is an example of metaphor in the memoir, Barbarian Days?

Surfing is a larger metaphor for life. Finnegan talks about the way in which little waves involve play and fun, but larger waves involve danger and violence. It is difficult to predict how any wave will go, though he spends a great deal of his life trying to "wire" or figure out certain beaches and hot spots for surfing. He is always on the hunt for the perfect wave, for something that will thrill him but not kill him. Surfing represents his religion, as he gave up the Catholicism that he practiced as a child. Instead, surfing filled that role for him.