In an attempt to clarify his earlier comment that he wouldn't want a Muslim in charge of the nation, Republican presidential hopeful Ben Carson explained that he takes issue with the core tenets of Islam, which he argues are "not compatible with our constitution."

On Sunday, ABC News "This Week" guest host Martha Raddatz asked Carson if he still stands by his last week's comment: "I would not advocate that we put a Muslim in charge of this nation."

The retired neurosurgeon responded,"I said anybody, doesn't matter what their religious background, if they accept American values and principles and are willing to subjugate their religious beliefs to our Constitution, I have no problem with them."

"What we should be talking about is Islam, and the tenets of Islam, and where do they come from?" Carson continued. "They come from Shariah. They come from the Quran. They come from, you know, the life works and examples of Muhammad [hadith]. They come from the fatwas, which is the writings of scholars."

Carson, who is the first choice of 20 percent of Republican primary voters according to a recent NBC poll, asserted,"You know, and if you go back and you look at - what I would like for somebody to show me is an improved Islamic text that opposes Shariah. Let me see - if you can show me that, I will begin to alter my thinking on this."

Carson asked, why should America take a chance "when you have something that is against the rights of women, against the rights of gays, subjugates other religions, and a host of things that are not compatible with our constitution."

The former neurosurgeon and bestselling author has been widely criticized for his original comments regarding Muslims, with one civil rights organization even calling on him to suspend his campaign.

However, in an email sent to supporters last week, Carson staunchly defended his stance: "These are my beliefs and I will not back down," he wrote in an email to supporters. "Many parts of Sharia Law are not compatible with the U.S. Constitution. Under Sharia, homosexuals -- men and women alike -- must be killed. Women must be subservient. And people following other religions must be killed as well."

He acknowledged that while there are "many peaceful Muslims who do not adhere to these beliefs," he cannot advocate any Muslim candidate for president "until these tenets are fully renounced."

Speaking to CNN's "State of the Union" host Jake Tapper on Sunday, Carson argued that the controversy surrounding his comments has been overblown. "Is it possible that maybe the media thinks it's a bigger deal than the American people do?" he said. "Because American people, the majority of them, agree and they understand exactly what I am saying."

He continued, "I've worked with Muslims. I've trained Muslims. I've operated on Muslims. There are a lot of Muslims who are very patriotic. Good Americans and they gladly admit, at least privately, that they don't accept shariah or the doctrines and they understand that Islam is a system of living and it includes the way that you relate to the government. And you cannot, unless you specifically, deny that portion of Islam be a Muslim in good standing. Now if that is the case, if you are not willing to reject that, then how in the world can you possibly be the president of the United States."