If a person follows all the required conditions: he studies authentic Kabbalah books, has the right teacher and the right environment, and he makes efforts, then his soul starts to be connected to the spiritual world. This connection is evoked by the Surrounding Light, and it affects him so that he gradually begins to receive new impressions. These impressions become greater and greater with time, until his sensation of the vague, Surrounding Light turns into a clear revelation of the obvious Inner Light.
Although a person started out with a desire that was a mere point of aspiration to the Creator, he now begins to feel a whole new reality through this desire. In this new sense, he perceives the Light that is now obvious to him. But it is the same Surrounding Light that previously shone to him in an imperceptible, concealed manner.
A person thus begins to see the Light’s actions and to work with It like with a partner. The period of concealment and preparation comes to an end, and a person begins to act with a clear perception of the spiritual world.
(From the Daily Kabbalah Lesson)