Answer: He obtains qualitatively new knowledge because now his revelation is part of him. In our world, I discover these or those external phenomena. For example, if I am a chemist, I observe, examine, and describe a chemical process.
In the science of Kabbalah, I reveal the upper world and am myself in the picture that opens to me. I am identical to my discovery; I have the same qualities that are there in the reality that I discover. Of course, at the same time, I see all the stages that I have passed, both spiritual and material. They remain in me, and I can descend to any of them to establish contact with others.
In general however, spiritual development is a precise attainment. I don’t just get to know or understand something. Knowing and attaining are not the same thing. Attainment means that I turn into the state that I have reached, not just becoming acquainted with a new degree, but become it.
From the 4th part the Daily Kabbalah Lesson 12/4/12, “Kabbalah and Philosophy”