Thing number 1: if you can instantaneously cure cancer and every other illness with a literal wave of your hand, why not make the world a better place and heal everyone instantaneously?
Thing number 2: if the success of the healing depends on the faith of the healee, where is the accountability when you fuck someone's life up and use the excuse they just didn't believe hard enough?
I respect spirituality and i understand that some people believe alternative therapies help them with things medical science doesn't - at the very least there's a comfort factor in believing the stuff is helping - but Jesus fuck. When i see my family sink hundreds of dollars into sessions and courses (courses!?) that teach them to blame their parents or some event in their childhood for their problems now that they should've been seeing a psychiatrist about years ago it just drives me nuts. You'd think after seeing all the shit i went through over the last 10 years they would've figured out that - surprise, surprise - medical science does actually work. The irony is that i've now ended up the sanest person in my family after all.
On a side-note, it also pisses me off when soon-to-be in-laws judge me for taking prescribed medication for my back because God forbid you take a drug that is actually proven to help instead of getting a hocus pocus massage. At least i have the respect for their beliefs that i don't take them to task for it - i just vent on LiveJournal. But i guess when you're relying on blind faith instead of evidence you also acquire a need to evangelize.