Quote from A Course in Miracles Text Chapter 4, Section 3 - The Ego and False Autonomy.

It cannot be emphasized too often that correcting perception is merely a temporary expedient. It is necessary only because misperception is a block to knowledge, while accurate perception is a steppingstone towards it. The whole value of right perception lies in the inevitable realization that all perception is unnecessary. This removes the block entirely. You may ask how this is possible as long as you appear to be living in this world. That is a reasonable question. You must be careful, however, that you really understand it. Who is the "you" who are living in this world? Spirit is immortal, and immortality is a constant state. It is as true now as it ever was or ever will be, because it implies no change at all. It is not a continuum, nor is it understood by being compared to an opposite. Knowledge never involves comparisons. That is its main difference from everything else the mind can grasp.

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