Originally published on Huffingtonpost.com

When Jeremy Affeldt started playing baseball, he hated San Francisco. As a conservative Christian, he bristled at the city's liberal ways–especially its embrace of homosexuality.

"I didn't leave my hotel room when we came to play the Giants or A's. I didn't want to go out or see anyone," he recently told The Associated Press.

As luck (or fate) would have it, he signed with none other than the San Francisco Giants in 2009. On the mound, Affeldt came out like a shot with a 28-inning scoreless streak in his first year with the team. And after recovering from an injury, he played a key role in winning both the 2010 and 2012 World Series for the Giants.

But his bigger transformation may have happened off the field. Affeldt, a lifelong advocate for social justice, began to reevaluate his mission, taking on some of San Francisco's biggest issues.

He became an ambassador for anti-human trafficking organization Not For Sale, and has inspired other athletes (including Giants pitcher Matt Cain) to do the same. And last week, Affeldt publicly repudiated his former homophobia, largely crediting San Francisco for his change of heart.

"I'll probably get a lot of flak from the church for it, but I believe I'm right," he said. "To see that and to have my heart change as a city I didn't ever want to come to, to a city that I'm so thankful I'm going to be part of for a long time. For me, it was an awesome deal."

Now he's detailed his life experiences in a new memoir To Stir A Movement: Life, Justice, and Major League Baseball. Affeldt sat down with The Huffington Post after a recent game to talk about baseball, the church's wrong turn and the city that's made him a better man.

Jeremy, you are a two-time World Series-winning pitcher. What in the world made you decide to write a book about social justice?
I love baseball, and I am so blessed to have the opportunity to play. But a baseball player is not who I am. When I first started playing pro ball I thought, "This is it?" Just pitching on the mound, going home and then pitching again? I know no one is crying for me, but I find that a shallow existence. If that's all there is, then you live and die with every win and loss. I wanted something bigger.

Do you think it's your responsibility to be a role model?
I hear a lot of athletes say they don't want to be role models. Well guess what? You are a role model. You may not be a good one, but you signed up for this. I want kids to view athletes positively. The four houses, the cars–that's not what I want to do with this money.

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