God is my Source. I cannot see apart from Him. Perception is not an attribute of God. His is the realm of knowledge. Yet He has created the Holy Spirit as the Mediator between perception and knowledge. Without this link with God, perception would have replaced knowledge forever in your mind. With this link with God, perception will become so changed and purified that it will lead to knowledge. That is its function as the Holy Spirit sees it. Therefore, that is its function in truth. In God you cannot see. Perception has no function in God, and does not exist. Yet in salvation, which is the undoing of what never was, perception has a mighty purpose. Made by the Son of God for an unholy purpose, it must become the means for the restoration of his holiness to his awareness. Perception has no meaning. Yet does the Holy Spirit give it a meaning very close to God's. Healed perception becomes the means by which the Son of God forgives his brother, and thus forgives himself. You cannot see apart from God because you cannot be apart from God. Whatever you do you do in Him, because whatever you think, you think with His Mind. If vision is real, and it is real to the extent to which it shares the Holy Spirit's purpose, then you cannot see apart from God. Three five-minute practice periods are required today, one as early and one as late as possible in the day. The third may be undertaken at the most convenient and suitable time that circumstances and readiness permit. At the beginning of these practice periods, repeat the idea for today to yourself with eyes open. Then glance around you for a short time, applying the idea specifically to what you see. Four or five subjects for this phase of the practice period are sufficient. You might say, for example: God is my Source. I cannot see this desk apart from Him. God is my Source. I cannot see that picture apart from Him. Although this part of the exercise period should be relatively short, be sure that you select the subjects for this phase of practice indiscriminately, without self-directed inclusion or exclusion. For the second and longer phase, close your eyes, repeat today's idea again, and then let whatever relevant thoughts occur to you add to the idea in your own personal way. Thoughts such as: I see through the eyes of forgiveness. I see the world as blessed. The world can show me myself. I see my own thoughts, which are like God's. Any thought related more or less directly to today's idea is suitable. The thoughts need not bear any obvious relationship to the idea, but they should not be in opposition to it. If you find your mind wandering; if you begin to be aware of thoughts which are clearly out of accord with today's idea, or if you seem to be unable to think of anything, open your eyes, repeat the first phase of the exercise period, and then attempt the second phase again. Do not allow any protracted period to occur in which you become preoccupied with irrelevant thoughts. Return to the first phase of the exercises as often as necessary to prevent this. In applying today's idea in the shorter practice periods, the form may vary according to the circumstances and situations in which you find yourself during the day. When you are with someone else, for example, try to remember to tell him silently: God is my Source. I cannot see you apart from Him. This form is equally applicable to strangers as it is to those you think are closer to you. In fact, try not to make distinctions of this kind at all. Today's idea should also be applied throughout the day to various situations and events that may occur, particularly to those which seem to distress you in any way. For this purpose, apply the idea in this form: God is my Source. I cannot see this apart from Him. If no particular subject presents itself to your awareness at the time, merely repeat the idea in its original form. Try today not to allow any long periods of time to slip by without remembering today's idea, and thus remembering your function.

- Jesus Christ in A Course in Miracles, Lesson 43