University of Pennsylvania's (UPenn) Anthea Butler wrote in a blog post that Americans worship a "white racist god with a problem," CampusReform.org reported.

Butler wrote the piece, published Sunday, on ReligiousDispatches.org, where she is a contributing editor. Butler is an associate professor of religious studies Africana studies, as well as the graduate chair of religious studies at UPenn.

"God ain't good all of the time. In fact, sometimes, God is not for us," she wrote. "As a black woman in a nation that has taken too many pains to remind me that I am not a white man, and am not capable of taking care of my reproductive rights, or my voting rights, I know that this American god ain't my god."

Butler, who carries a master's in theology and PhD in religion, argued in her opinion piece that Christianity is one of America's biggest proponents of racism.

"When George Zimmerman told Sean Hannity that it was God's will that he shot and killed Trayvon Martin, he was diving right into what most good conservative Christians in America think right now," she wrote.

Butler also claimed that the "moment" at the center of the trial was one of deep-seeded racism in American history.

"As a historian of American and African-American religion, I know that the Trayvon Martin moment is just one moment in a history of racism in America that, in large part, has its underpinnings in Christianity and its history," she wrote.

She closed her piece by saying she was responsible for telling even the ugly parts of the story.

"Those of us who teach American Religion have a responsibility to tell all of the story, not just the nice touchy-feely parts," she wrote. "When the good Christians of America are some of its biggest racists, one has to consider our moral responsibility to call out those who clearly are not for human flourishing, no matter what ethnicity a person is. Where are you on that scale? I know where I am."