Alabama Republican Senate nominee Roy Moore on Tuesday stood by his decades-old statement that Muslims should not be allowed to serve in Congress, Mediaite reported.

"Read my article and you'll find out what I believe," he told MSNBC reporter Garrett Haake while on the Senate floor. "It's clarified very clearly in my article."

Moore, a former Alabama chief justice, has made a number of controversial statements in the past. In 2006, he urged Congress to bar Keith Ellison, the first Muslim elected to Congress, from being sworn in because he would be taking his oath with his hand on a Quran and not a Bible.

"Common sense alone dictates that in the midst of a war with Islamic terrorists we should not place someone in a position of great power who shares their doctrine," Moore wrote on WorldNetDaily.com. "In 1943, we would never have allowed a member of Congress to take their oath on Mein Kampf, or someone in the 1950s to swear allegiance to the 'Communist Manifesto.' Congress has the authority and should act to prohibit Ellison from taking the congressional oath today!"

Last year, Moore said the legalization of gay marriage was worse than a 19th century Supreme Court case that upheld slavery.

GOP Sen. Jeff Flake of Arizona said Moore's views "should concern us all."

"When a judge expressed his personal belief that a practicing Muslim should not be a member of Congress because of his religious faith, it was wrong. That this same judge is now my party's nominee for the Senate from Alabama should concern us all," Flake said during a speech on the Senate floor, according to a report in The Hill.