I resent that notion because it takes a perfectly reasonable proposition, i.e., we are a holistic mechanism, and reduces the complexity of this reality to a smug, New Age motto which goes roughly like this: "If you think the right thoughts, you'll be physically healthy."
The assumption here is that (a) it's even possible to think all the right thoughts, all the time and (b) that it is a sign of advanced spiritual maturity to do so.
I am a Jungian, and respect the deep powers of the unconscious. To try to think all the right thoughts is, in my opinion, nothing but a grand exercise in egotism and control. People who try to think all the right thoughts all the time scare me. By willing themselves to jump immediately from, say, anger or jealousy or fear right to acceptance or compassion, they are not honoring their humanity but controlling it. They are not enlightened. They are tight-clenched control freaks.
Even the greatest teachers of peace and compassion never counsel such discipline. They say, rather (and it's a fine distinction), that we should observe our humanity with compassion, meditate in order to clear our minds of its constant and grievous chatter, and that we should not react out of a base survival instinct but out of our compassionate nature. In other words, we don't eradicate neurotic, typically human reactions but gain the maturity to observe and respect their origins, and to allow a higher, subsequent understanding to inform our actions and responses.
I am speaking mostly from my small store of knowledge of Buddhism here, but it seems to me that Jesus had some pretty snappy, judgmental first responses to people, too, but then inevitably put out his hands for the healing and blessing that was requested. He was far from being the ethereal bliss-ninny he is often depicted as being. When he said, "Your faith has made you well," he was not rewarding "thinking the right thoughts," but, in fact, overcoming the prevalent attitude toward disease in ancient times, which was that affliction is caused by sin as a punishment from God. To me, "your faith has made you well" is a congratulations similar to the one delivered in the beatitudes: "Blessed are those who, despite the ignorant teachings of their culture, know themselves to be deserving of healing and will seek it."
As far as sick thoughts and sick bodies go, it strikes me as appallingly unfair to hold cancer patients (as one example) responsible for their condition. While it may be that a lifetime of resentment and rage and keeping poisonous secrets damage the body's strength and immunity, to fail to factor in environmental toxins and genetic predisposition to such diseases is beyond irresponsible, it is hateful.
That said, I have been dealing with a very painful out-of-wack lower back for a few days now and while I know that the obvious factor is the overloading of my weights two weeks ago (my trainer accidentally loaded an extra 65 lbs. on the lower back circuit weight), I also resonate with an idea I think Wally Nut suggested, which is that lower back problems might flare up when we don't feel supported.
Sure there are other factors: bad muscle tone and overweightness, too many hours sitting at the computer, flinging around of 20-lb. kitty litter canisters, hefting full laundry baskets up the stairs in bad form, and having a 1.5 hour work-out without stretching or warming up first. But the timing of such a thing is unmistakably emotionally-connected, too.
As a result, I'm not at all trying to think the right thoughts, but to move slowly through the days as actively as possible, seeking support where I need it, assuming I'll be perfectly fine in a matter of days, and above all, holding myself and my creaky self with compassion rather than blame.