Houston Texans running back Arian Foster is a lot of things - a football player, a husband, a father. But what most people don't know about Foster is that he's also an atheist. And perhaps more importantly than that, he's a proud atheist.

"A lot of it has to do with the way that Arian was brought up," ESPN The Magazine senior writer Tim Keown said. Keown wrote an in-depth piece recently, which delves into Foster's upbringing - he was raised Muslim, has spent time learning from both the Quran and the Bible - and the reasoning behind his now-firm belief in science over religion.

"Everybody always says the same thing: You have to have faith," Foster says in the piece. "That's my whole thing: Faith isn't enough for me. For people who are struggling with that, they're nervous about telling their families or afraid of the backlash ... man, don't be afraid to be you. I was, for years."

Foster, of course, has spent nearly his entire football career performing in the Bible belt. He played collegiately at Tennessee and is now a member of the Houston Texans. Despite this and his therefore close relationships with many, many people of faith, Foster has decided to become something of a spokesperson for the nonreligious by joining forces with the nonprofit group Openly Secular.

"This is unprecedented," said Todd Stiefel, chair of Openly Secular, per Keown. "He is the first active professional athlete, let alone star, to ever stand up in support of gaining respect for secular Americans."

According to the Pew Research Center, between 2007 and 2014, the Christian share of the general U.S. population fell from 78.4 percent to 70.6 percent, while the percentage of Americans who do not identify with any religion has jumped six percent, from 16.1 percent to 22.8 percent.

While Foster makes clear in the piece that he understands the sensitivity of the topic, especially considering he plays in Houston, which is home to deeply rooted Christian communities, but that in the end, he feels he needs to be true to himself.

"You don't want to ruin endorsements," he says. "People might say, 'I don't want an atheist representing my team.' Now, though, I'm established in this league, and as I'm digging deeper into myself and my truth, just being me is more important than being sexy to Pepsi or whoever. After a while, what's an extra dollar compared to the freedom of being you? That's the choice I made."

Foster credits his father, Carl Foster - who Arian deems "a free thinker" - with encouraging him to question conventions despite the fact that Carl was a deeply religious man.

Still, Foster simply wants to be free to believe what he believes at the same time as the religious among us are afforded the same opportunity.

"If a loving, kind Christian, Muslim or Jewish person can't accept a different vantage point, there's just nothing I can do about it," Foster says. "I have no ill will toward religion or religious people. I have no quarrels. Believe what you want to believe."