I am the light of the world.

Who is the light of the world except God's Son? This, then, is merely a statement of the truth about yourself. It is the opposite of a statement of pride, of arrogance, or of self-deception. It does not describe the self-concept you have made. It does not refer to any of the characteristics with which you have endowed your idols. It refers to you as you were created by God. It simply states the truth.
To the ego, today's idea is the epitome of self-glorification. But the ego does not understand humility, mistaking it for self-debasement. Humility consists of accepting your role in salvation and in taking no other. It is not humility to insist you cannot be the light of the world if that is the function God assigned to you. It is only arrogance that would assert this function cannot be for you, and arrogance is always of the ego.
True humility requires that you accept today's idea because it is God's Voice Which tells you it is true. This is a beginning step in accepting your real function on earth. It is a giant stride toward taking your rightful place in salvation. It is a positive assertion of your right to be saved, and an acknowledgment of the power that is given you to save others.
You will want to think about this idea as often as possible today. It is the perfect answer to all illusions, and therefore to all temptation. It brings all the images you have made about yourself to the truth, and helps you depart in peace, unburdened and certain of your purpose.
As many practice periods as possible should be undertaken today, although each one need not exceed a minute or two. They should begin with telling yourself:

I am the light of the world. That is
my only function. That is why I am here.

Then think about these statements for a short while, preferably with your eyes closed if the situation permits. Let a few related thoughts come to you, and repeat the idea to yourself if your mind wanders away from the central thought.
Be sure both to begin and end the day with a practice period. Thus you will awaken with an acknowledgment of the truth about yourself, reinforce it throughout the day, and turn to sleep as you reaffirm your function and your only purpose here. These two practice periods may be longer than the rest, if you find them helpful and want to extend them.
Today's idea goes far beyond the ego's petty views of what you are and what your purpose is. As a bringer of salvation, this is obviously necessary. This is the first of a number of giant steps we will take in the next few weeks. Try today to begin to build a firm foundation for these advances. You are the light of the world. God has built His plan for the salvation of His Son on you.

- Jesus Christ in A Course in Miracles, Lesson 61