This is from Husserl's Phenomenology, an article he wrote for the Encyclopedia Britannica:
Together with this philosophical phenomenology, but not yet separated from it, however, there also came into being a new psychological discipline parallel to it in method and content: the a priori pure or “phenomenological” psychology, which raises the reformational claim to being the basic methodological foundation on which alone a scientifically rigorous empirical psychology can be established. An outline of this psychological phenomenology, standing nearer to our natural thinking, is well suited to serve as a preliminary step that will lead up to an understanding of philosophical phenomenology.
Husserl is claiming that phenomenology is the “basic methodological foundation on which alone a scientifically rigorous empirical psychology can be established.” Why is this a reformational claim?
