Fox's Neil Cavuto asks Ben Carson: Does God prefer your plan, or Donald Trump's?

Fox Business Network moderator Neil Cavuto questioned retired neurosurgeon Ben Carson during Tuesday night's debate about his tax plan.

Carson, a Seventh-day Adventist who frequently discusses his faith on the campaign trail, has suggested he would adopt "tithing" across the board, referring to the Biblical system in which one-tenth of a person's income was given to the church.

"You say you are in favor of a tax system, I guess, akin to tithing, sir, with a flat tax rate of up to 15%," Cavuto said. "Because you said, 'If everybody pay this, I think God is a pretty fair guy do tithing is a pretty fair process.'"

"But Donald Trump says that is not fair, that wealthier tax payers should pay a higher rate because it's a fair thing to do," Cavuto added. "So whose plan would God endorse then, doctor? Yours, or Mr. Trump's?"

Carson didn't address the either-or question, but he said his "tithing" argument is based on proportionality.

"Well, when I say 'tithing' I'm talking about the concept of proportionality," Carson said. "Everybody should pay the same proportion of what they make. You make $10 billion, you pay $1 billion. You make $10, you pay $1. You get the same rights and privileges. I don't see how anything gets a whole lot fairer than that."

Carson has said in the past that he would make up a potential revenue gap by cutting spending strategically.