A treatment is a spiritual entity in the mental world and is equipped with power and volition—as much power and volition as there is faith in it, given to it by the mind of the one using it—and, operating through the Law, It knows exactly how to work and what methods to use and just how to use them. We do not put the power into this word, but we do let the power of the Law flow through it, and the one who most completely believes in this power will produce the best results. This is the Law of cause and effect, again.
When one gives a treatment for right action, and does not believe that right action will be the result, he makes his own treatment negative. Therefore, we should spend much time in convincing ourselves of the truth of our treatments. Now this is not a power of will, but a power of choice. We do not put the power into the treatment, and we will take out of the treatment ONLY AS MUCH AS WE BELIEVE IS IN IT!
If one doubts his ability to give an effective treatment, he should specifically treat himself to remove this doubt. He should say something like this, but not necessarily these words: “I am convinced that this word has power, and I firmly believe in it. I trust it to produce the right results in my life, (or in the life of the one for whom I am using my word).”
We should work, not with anxiety but with expectancy; not by coercion but with conviction; not through compulsion but in a state of conscious recognition and receptivity. We do not have to drive or push but we must accept and believe. We should, then, leave everything to the Law, expecting a full and complete proof of our faith. We shall not be disappointed nor chagrined, for the Law is our faithful servant.
Holmes, Ernest (1998-08-24). The Science of Mind: The Definitive Edition (pp. 58-59). Penguin Group. Kindle Edition.