It's worth mentioning again. The discussion of faith between presidential hopefuls Barack Obama and John McCain will begin tomorrow at Saddleback Church.

According to the Boston Globe, Rick Warren will interview the presidential hopefuls for an hour each, back to back Saturday night in a forum that will be broadcast live by the cable networks.

And the broadcasting has already begun today with Warren making the rounds of television morning shows.

What will McCain say? The Chicago-Tribune published a faith-focused interview today recounting McCain's efforts to organize religious services while a prisoner of war from 1967 to 1973 in Vietnam.

Now, however, he maintains that his faith is private, but that it informs his decisions on issues of public policy.

Reports today also inform us that McCain was brought up Episcopalian but now worships at a Southern Baptist church in Phoenix.

Obama reportedly became a Christian as an adult, but during the campaign left his church home, Trinity United Church of Christ in Chicago, after repudiating the former pastor, the Rev. Jeremiah A. Wright Jr., over explosive remarks from the pulpit about race and the US government.

So, what is the spiritual story for these presidential candidates today? We may find out tomorrow. Then again, we may not. Warren has said his focus for the interview will be about the issues that compelled him to create the P.E.A.C.E. Plan for global outreach. So we may hear more about poverty, America's responsibility to the developing world, and HIV/AIDS than faith.

"We're going to look at leadership, specifically their character, their competence, their experience," Warren told ABC News in an interview for "Good Morning America."

"I want to give America a better, closer look at the two candidates. I think we want to see not just their values, but their vision, their virtues," he said.

But Warren won't let either man get away without answering the pivotal question for evangelicals, whose vote is being highly sought-after: Who is Jesus Christ to you?

While that may be a preacher's question, an evangelical believer's question, I wonder, is it the pivotal question for Christian voters who must decide between these two men in the upcoming election? Is a fellow-believer whose politics are different than your own worthy of a vote?

And perhaps the larger looming question: Is anyone but Christ himself really qualified to judge the spiritual state of anyone?

"Both of these men care about America," The Los Angeles Times quoted Warren as saying. "My job is to let them share their views."

Another question here. Is that really Warren's job? After all the book sales, world travel and church rejuvenation work, he is a church pastor after all.

Warren explained that this interview and his church entertaining other prominent politicians of various platforms has all been his attempt to introduce civility into public discourse. Now that is laudable. Is it part of an incredibly thorough job description for church leadership? I don't know.

Warren certainly understands leadership—even leading gigantic organizations. So he will undoubtedly have some insight into the leadership strengths and weaknesses of these men. I doubt he will share that insight, however, as he has said (wisely) that he will not endorse anyone.

Still, it should prove to be a very interesting Saturday at Saddleback.