Quote from A Course in Miracles Text Chapter 2, Section 5 - The Function of the Miracle Worker.

The fear of healing arises in the end from an unwillingness to accept unequivocally that healing is necessary. What the physical eye sees is not corrective, nor can error be corrected by any device that can be seen physically. As long as you believe in what your physical sight tells you, your attempts at correction will be misdirected. The real vision is obscured, because you cannot endure to see your own defiled altar. But since the altar has been defiled, your state becomes doubly dangerous unless it is perceived.

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