A belief system does help one to do better meditation, be it a belief in spiritual power (which my friend did), or a motivation to persistency in practice (which my friend failed). For me, I like to work with "suspension of disbelief", or "visualization". When we "honestly" visualize, or "honestly" respect spiritual power, our body and mind will respond appropriately. Every actor knows the art, and everybody can learn the art. The beauty of "suspension of disbelief" allows an actor, or a meditator, to benefit yet not to create conflict with his existing belief system, religious or spiritual. Having said that, it still begs the question: Certainly believer and meditator are two different persona or roles, one cannot and should not confuse one from another. Our skeptics has his point.
With the right "suspension of disbelief", our body and mind will relax. And with mind-body relaxation, one can create a chi-gradient or Yin-yang contrast by stretching certain point of our body, notable, our hands and fingers by stretching them. Now we have the mechanics work out right. What is the next "task" of the meditator? The classic opinion is Wait! But wait for what?
Firstly, the meditator has to wait patiently until chi arises. The more relaxed one's mind and body, the quicker and stronger will be one's chi generation. Initially chi will be generated in the stretched hands, and gradually chi can be felt in other part(s) of the body, including the lower abdomen.
Secondly, and the major task of the meditator, the meditator has to subtly use his mind and body to move his chi from the more concentrated area (like his stretched hand or abdomen) to other parts of his body. In essence: equalization. This task occupies most of the time of one's meditation session. By taking on this task, a meditator trains/transform his mind and body at the same time.
Spirituality or "a suspension of disbelief" leads a person towards meditation, but it is NOT the mechanics of meditation, as I have explained above.