There's no doubt that much of what Rush says appeals to religious conservatives. Both favor Republicans, limited government, abortion limits, a strong military, and religious freedom in the public square.
But beyond sharing a common political philosophy (religious liberals would say that is plenty enough!), I'm not sure what else Rush and religious conservatives have in common--especially when it comes to religious convictions.
Talk show and TV host Sean Hannity freely identifies himself as Catholic, but to my knowledge Rush has never said outright that he is a Christian or a follower of Jesus Christ. While Rush consistently defends the rights and beliefs of religious conservatives (leading many to think he must be a Christian), if you listen carefully you'll find that Rush keeps his personal beliefs about God very close to the vest.
After all I've heard him say, I would describe Rush as a God-fearing man. No more. No less.
Hannity has talked many times to Focus on the Family's James Dobson, but I've never read or heard Rush interview popular religious conservatives like Dobson or other people--like Southern Baptists Albert Mohler and Jerry Falwell--that the media typically looks to for a controversial quote. I've never seen pictures of Rush with any of these types either. The reason is Rush doesn't attend their events.
Limbaugh proudly smokes cigars, boasts a little too much about himself, and relishes his wads of cash--something religious conservatives wouldn't like their flock doing.
On Sundays, I get the impression that Rush enjoys his recluse life at home in Florida, watches lots of the TV (especially during the NFL season), or is out playing golf with friends. Again, religious conservatives would rather see their flock at church on Sundays.
Limbaugh and religious conservatives are political allies, but beyond that, I don't see anyplace else where their worlds intersect.