There are two kinds of faith, … Like Freedom there is the kind which is easily kept but proves not worth the keeping, and there is a kind which is hard-won."
I think Aikido depends very much on the latter.
In one case, as one begins to progress in the Way, one must begin to do a lot of "soul-searching" on the meaning of harmony, love and what is the true meaning of the art of peace, and the answer is different and personal for every artist.
In another case, I'm sure there are a lot of scholars (religious and secular) on this board who are more better equip to explain how's one faith, disposition, intent, has an effect on involuntary muscular tension, posture, and demeanor. All of which have an effect on one's performance.
Lastly, one's faith, perceptual filters, has a strong influence in how we as individuals relate to the world, and interact with our partners.
For myself all of these things make up one's faith, whether it is in Science, Allah or the Tao.