The Freedom From Religion Foundation (FFRF) filed a federal lawsuit Wednesday to prevent Texas Republican Governor Rick Perry from taking part in a planned evangelical Christian prayer rally he initiated in Houston.

Perry proclaimed August 6 as a "Day of Prayer and Fasting for our Nation to seek God's guidance" and invited governors from across the nation to join his Christian prayer summit at Reliant Stadium.

"Given the trials that beset our nation and world, from the global economic downturn to natural disasters, the lingering danger of terrorism and continued debasement of our culture, I believe it is time to convene the leaders from each of our United States in a day of prayer and fasting, like that described in the book of Joel," Perry said in June.

The legal complaint asks the federal court to declare unconstitutional Perry’s organization, promotion and participation in the event because it violates the Establishment Clause of the First Amendment.

It says Perry's active participation in the event violates the U.S. Constitution by “giving the appearance that the government prefers evangelical Christian religious beliefs over other religious beliefs and non-beliefs, including by aligning and partnering with the American Family Association, a virulent, discriminatory and evangelical Christian organization known for its intolerance.”

The website for the prayer summit says that Americans "must come together and call upon Jesus to guide us through unprecedented struggles" because "some problems are beyond our power to solve."

The event is co-hosted by the American Family Association, a fringe conservative Christian group that advocates the reform of American culture based on their interpretation of the Bible. FFRF said the association "promotes a rabid evangelical Christian agenda that is hostile to non-believers, non-Christians and other protected groups, such as gays and lesbians."

The FFRF's legal complaint also alleges that Perry has embraced the views of the American Family Association.

The Director of Issue Analysis for Government and Public Policy at the American Family Association once proclaimed that "homosexuality gave us Adolph Hitler [sic], and homosexuals in the military gave us the Brown Shirts, the Nazi war machine and six million dead Jews."

Bryan Fischer is no stranger to outlandish comments, such as claiming WikiLeaks shows that gays shouldn't be allowed in the military and warning President Barack Obama would hand over the entire land mass of the U.S. to Native Americans. In March, he said the right to freedom of religion guaranteed in the Constitution does not apply to Muslims.

On Tuesday night, MSNBC host Rachel Maddow showed a series of clips of evangelical Christian preachers who are participating in Perry's prayer summit. One preacher participating in the event has said that the stock market in Japan fell because the emperor had sex with a “sun goddess” demon. Another has proclaimed that Lady Liberty is actually a "demonic idol" meant to distract Americans from Christ.

"We always say 'Beware prayer by pious politicians,'" said Annie Laurie Gaylor, who co-directs FFRF. "Nothing fails like prayer. It’s the ultimate political cop-out."

"The answers for America’s problems won’t be found on our knees or in heaven, but by using our brains, our reason and in compassionate action,” said her husband and FFRF co-director Dan Barker. "Gov. Perry’s distasteful use of his civil office to plan and dictate a religious course of action to ‘all citizens’ is deeply offensive to many citizens, as well as to our secular form of government."

Perry is the longest-serving governor in Texas history and is considering making a run for the 2012 Republican presidential nomination. In April, he issued an official proclamation urging Texans to pray for rain in the midst of a severe drought that had sparked more than 8,000 wildfires. Last year, he said the oil spill in the Gulf of Mexico might have been an "act of God" that would have occurred regardless of safety regulations.