C.S. Lewis said 'You cannot go on explaining away
for ever', i.e. there has to be something at the root of what we believe. In Breaking the Spell
Daniel Dennett seems to have turned this argument back on itself, saying in effect, OK if that's the case then it won't harm for us to go on trying to explain things such as religion. I can't help thinking that he's trying to pull a fast one myself (if you can use the word 'fast' in relation to Dennett's long books). But if you're interested in the status of religion then it's definitely worth taking a look at this book.
I would say however that although the stated aim of the book is to justify the scientific examination of religion, Dennett does seem to be trying to do other things as well. One is to improve the status of atheists (or 'brights') in the USA, and another is to impress on the more moderate members of religions that they have a responsibility to keep the more extreme factions in check. This means that there is less space to devote to the central argument. Dennett describes the work of previous writers who have supported this argument, but there doesn't seem to be much mention of their critics (who I'm sure must exist). I found this rather surprising, as a hallmark of Dennett's books on consciousness is detailed replies to critics of his ideas