Complex sentence: Silkworth believed Wilson was making a mistake by telling new converts of his "Hot Flash" conversion experience as well as trying to apply the Oxford Group's principles and advised Wilson of the need to deflate the alcoholic.
Split into simpler sentences: Silkworth believed Wilson was making a mistake by telling new converts of his "Hot Flash" conversion and trying to apply the Oxford Group's principles. He advised Wilson of the need to deflate the alcoholic.