Quote from A Course in Miracles Text Chapter 5, Section 3 - The Voice for God.

The Holy Spirit is your Guide in choosing. He is in the part of your mind that always speaks for the right choice, because he speaks for God. He is your remaining communication with God, which you can interrupt but cannot destroy. The Holy Spirit is the way in which God's Will is done on earth as it is in heaven. Both heaven and earth are in you, because the call of both is in your mind. The voice for God comes from your own altars to him. These altars are not things; they are devotions. Yet you have other devotions now. Your divided devotion has given you the two voices, and you must choose at which altar you want to serve. The call you answer now is an evaluation because it is a decision. The decision is very simple. It is made on the basis of which call is worth more to you.

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