As the third Republican presidential debate approaches and the field narrows, Donald Trump and Ben Carson once again feud over religious beliefs in an attempt to sway uncertain voters in what is turning out to be a neck-and-neck race for the GOP polls in Iowa.

Ben Carson, a Seventh-day Adventist, was asked by a reporter last month how he was different from candidate Donald Trump. Carson’s answer was short and direct, stating, “Probably the biggest thing — I’ve realized where my success has come from and I don’t in any way deny my faith in God.”

Carson’s comment was made in light of some recent queries about Trump’s faith, even though Trump professes to be a Presbyterian. Earlier in the summer Trump said in an interview that he has never sought forgiveness from God, and went on to say that, “I think if I do something wrong, I think I just try and make it right. I don’t bring God into that picture.”

Donald Trump reacted to Carson’s statement by tweeting, “Wow, I am ahead of the field with Evangelicals (I am so proud of this) and virtually every other group, and Ben Carson just took a swipe at me.” Trump also had an interview the next morning on CNN’s New Day morning show, and took another swipe at Carson by saying, “If you look at his past, which I’ve done, he wasn’t a big man of faith. All of a sudden he’s becoming this man of faith and he was heavy into the world of abortion.” Carson later apologized for his comment that started the feud, but not before Trump retaliated by calling Carson an “okay doctor.”

However, this last week it was Trump who went after Carson’s religious beliefs in a campaign speech given in Florida. Trump was quoted as saying, “I’m Presbyterian. Boy, that’s down the middle of the road, folks, in all fairness. I mean, Seventh-day Adventist, I don’t know about it. I just don’t know.”

Trump then said that he saw no need to apologize when he was criticized for his comments, stating, “I would certainly give an apology if I said something bad about it. But I didn’t. All I said was I don’t know about it.” Carson was asked about the comments in a Fox News interview, but avoided a direct response, saying instead that “I really refuse to really get into the mud pit,” adding also that Trump “is who he is. I don’t think that’s going to change. And I am who I am. That’s not going to change, either.”

In fact, Carson said the whole religious argument that began the rivalry was a misunderstanding, and that he feels bad that Trump thought he was attacking him at all. “I would like to say to him that the intention [of the religious comment] was not to talk to him but about what motivates me. If he took that as a personal attack on him, I apologize, it was certainly not the intent.”

It is now Carson’s goal to avoid political drama and focus on having a positive and respectful campaign that puts an intense focus on his compelling life story. “Everyone is going to be saying, ‘Oh there’s a big fight, everyone come watch the fight,’” said Carson. “But it’s just not going to be as great as they think, because I’m not going to participate.”