Update (with a more complete quote): Willis comments on religion in an interview in the July 1998 issue of George magazine.
"Organized religions in general, in my opinion, are dying forms," he says. "They were all very important when we didn't know why the sun moved, why weather changed, why hurricanes occurred, or volcanoes happened," he continues. "Modern religion is the end trail of modern mythology. But there are people who interpret the Bible literally. Literally!" he says incredulously. "I choose not to believe that's the way. And that's what makes America cool, you know?"
Talks about how this life is all there is: http://www.contactmusic.com/new/xmlfeed.nsf/mndwebpages/willis%20obsessed%20with%20death