Answer: We process and take into account the attributes, the thoughts, and the actions that show us the incorrect form without disrespecting it and at the same time we build our Partzuf with them. The form by which we discover the Creator is made from both Light and darkness.
Our vessels of perception cannot perceive things differently since we are created beings that are made of the desire to receive, of the darkness. Therefore we need both the darkness and the Light. By chewing and swallowing the bitter herbs (Maror) we establish this contrast that allows us to perceive all the discernments of the Light.
There are no forms in the Light itself, so it is impossible to feel anything without the discernments that we collect. A new sensation comes and suddenly we begin to understand and to feel more and more and to see through the reality that becomes transparent. It is because up until now we found it hard and practically impossible to connect, to understand, to feel, and were confused. This is the only way the revelation happens: We perceive the contrast between the black and the white.
But we begin to perceive the black Light just like the white Light as we understand that without it we cannot exist. The desire to receive becomes as important as the Light.
From the 3rd part of the Daily Kabbalah Lesson 4/16/14, Writings of Rabash