a) “Correction of a lasting nature,—and only this is true correction,—cannot be made until the teacher of God has ceased to confuse interpretation with fact, or illusion with truth. ²If he argues with his pupil about a magic thought, attacks it, tries to establish its error or demonstrate its falsity, he is but witnessing to its reality.” (ACIM, M-18.1:1-2)
b) “⁷You but mistake interpretation for the truth. ⁸And, you are wrong. ⁹But, a mistake is not a sin, nor has reality been taken from its throne by your mistakes. ¹⁰God reigns forever, and His laws alone prevail upon you and upon the world. ¹¹His Love remains the only thing there is. “¹²Fear is illusion, for you are like Him.” (ACIM, M-18.3:7-12)
c) “In order to heal, it thus becomes essential for the teacher of God to let all his own mistakes be corrected. ²If he senses even the faintest hint of irritation in himself as he responds to anyone, let him instantly realize that he has made an interpretation that is not true. ³Then let him turn within to his eternal Guide and let Him judge what the response should be. ⁴So is he healed, and in his healing is his pupil healed with him. ⁵The sole responsibility of God’s teacher is to accept the Atonement for himself. ⁶Atonement means correction, or the undoing of errors. ⁷When this has been accomplished, the teacher of God becomes a miracle worker by definition. ⁸His sins have been forgiven him, and he no longer condemns himself. ⁹How can he then condemn anyone?¹⁰ And who is there whom his forgiveness can fail to heal?” (ACIM, M-18.4:1-10)
This mental process of checking our old mindset and instead reaching out to the Force (the Holy Spirit, our Creator) to work through us and guide us is the habit we must develop. This is how correction is made.