Conservative commentator Bill O'Reilly on Tuesday endorsed the arguments of gay marriage advocates.

In a discussion with Fox News personality Megyn Kelly on The O'Reilly Factor, O'Reilly agreed with his guest, saying that the “compelling argument is on the side of homosexuals.”

Kelly explained why she thought Americans' views were changing on the issue of marriage equality.

“Because I think the same-sex marriage advocates have done a credible job in getting out there and making their case,” Kelly said. “I mean, for years those who opposed gay marriage, take the religious piece out of it for this, because there is no arguing that. The Christian religion teaches what it teaches. The Bible says what it says. I mean about marriage.”

“But our policy shouldn't be made by that.”

“I had an interview with Tony Perkins of the [Christian conservative] Family Research Council. What is it about calling a gay union a marriage that offends you. How does it hurt traditional, or heterosexual marriage? And I didn't hear anything articulated that was particularly persuasive.”

“And I agree with you 100 percent,” O'Reilly said. “The compelling argument is on the side of homosexuals. That's where the compelling argument is. 'We're Americans, we just want to be treated like everybody else.' That's a compelling argument. And to deny that, you've got to have a very strong argument on the other side. And the other side hasn't been able to do anything but thump the Bible.”

Talk show host Rush Limbaugh criticized O'Reilly's remarks, saying that he had “marginalized” Fox News viewers.