Quote from A Course in Miracles Text Chapter 5, Section 4 - The Guide to Salvation.

The Holy Spirit is the idea of healing. Being thought, the idea gains as it is shared. Being the Call for God, it is also the idea of God. Since you are part of God it is also the idea of yourself, as well as of all his creations. The idea of the Holy Spirit shares the property of other ideas because it follows the laws of the universe of which it is a part. It is strengthened by being given away. It increases in you as you give it to your brother. Your brother does not have to be aware of the Holy Spirit in himself or in you for this miracle to occur. He may have dissociated the Call for God, just as you have. This dissociation is healed in both of you as you become aware of the Call for God in him, and thus acknowledge Its being.

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