God is the strength in which I trust.

If you are trusting in your own strength, you have every reason to be apprehensive, anxious and fearful. What can you predict or control? What is there in you that can be counted on? What would give you the ability to be aware of all the facets of any problem, and to resolve them in such a way that only good can come of it? What is there in you that gives you the recognition of the right solution, and the guarantee that it will be accomplished?
Of yourself you can do none of these things. To believe that you can is to put your trust where trust is unwarranted, and to justify fear, anxiety, depression, anger and sorrow. Who can put his faith in weakness and feel safe? Yet who can put his faith in strength and feel weak?
God is your safety in every circumstance. His Voice speaks for Him in all situations and in every aspect of all situations, telling you exactly what to do to call upon His strength and His protection. There are no exceptions because God has no exceptions. And the Voice Which speaks for Him thinks as He does.
Today we will try to reach past your own weakness to the Source of real strength. Four five-minute practice periods are necessary today, and longer and more frequent ones are urged. Close your eyes and begin, as usual, by repeating the idea for the day. Then spend a minute or two in searching for situations in your life which you have invested with fear, dismissing each one by telling yourself:

God is the strength in which I trust.

Now try to slip past all concerns related to your own sense of inadequacy. It is obvious that any situation that causes you concern is associated with feelings of inadequacy, for otherwise you would believe that you could deal with the situation successfully. It is not by trusting yourself that you will gain confidence. But the strength of God in you is successful in all things.
The recognition of your own frailty is a necessary step in the correction of your errors, but it is hardly a sufficient one in giving you the confidence which you need, and to which you are entitled. You must also gain an awareness that confidence in your real strength is fully justified in every respect and in all circumstances.
In the latter phase of the practice period, try to reach down into your mind to a place of real safety. You will recognize that you have reached it if you feel a sense of deep peace, however briefly. Let go all the trivial things that churn and bubble on the surface of your mind, and reach down and below them to the Kingdom of Heaven. There is a place in you where there is perfect peace. There is a place in you where nothing is impossible. There is a place in you where the strength of God abides.
During the day, repeat the idea often. Use it as your answer to any disturbance. Remember that peace is your right, because you are giving your trust to the strength of God.

- Jesus Christ in A Course in Miracles, Lesson 47