Faith is a belief that is grounded on no evidence.
Memorizing religious doctrine means it will stay the same over time - paraphrasing makes it easier to change the meaning. This is why religious doctrine is purposely so vague.
The onus lies with the person making the claim to prove its existence, not with the person refuting the claim.
The ultimate proof of God's existence is to have the most grandchildren.
The Convergence of Intelligences
American Heart Journal study of the therapeutic effects that intercessory prayer has on coronary bypass patients.
NY Times article on the study.