http://1stholistic.com/prayer/hol_prayer_proof.htm
As
this page of your source indicates, 1stholistic.com has an extremely broad definition of prayer consistent with various forms of meditation and a variety of non-Christian practices. I'm not arguing whether meditation works or not -- it has demonstrable effects on the brain. Further, the second paragraph of
this page indicates that the dumb quacks conflate the health benefits of religiosity with the efficacy of prayer. They also can't be bothered to write in proper English ("This is
thew situation when the sick persons are prayed for and don't even know it.", fifth paragraph) and cite the "parapsychological literature" in arguing that prayer makes prayed-for fungi grow faster (fifth bullet down). These are the people whose word you want to take?
It's clear that you've desperately googled 'prayer works' or some such and linked me to whatever came up. The problem is, this is a quack-laden site that doesn't even address the concept of prayer you have in mind. The fact remains that all major, scientific studies of Christian intercessory prayer indicate zero efficacy.
So, how did you end up believing something with no evidence that you must've known at some level you had no evidence for? It couldn't be that evidence doesn't matter in the end and that you choose beliefs based on their ability to satisfy preferences and look for evidence after the fact, if at all?