What does it mean to fix your thoughts?

As you permit your consciousness to dwell amid the confusion of world thought, these seek to overpower your own individual thoughts of oneness with the divine.

Try your best to fix your thoughts upon these two things—

First, say to yourself—

I am a child of God—One with my Father. 

My divine Mother is love. 

My divine life is the Christ. 

I am one with all this, and I can, and must, draw my thought-force from this source.

The second is—

Since I am a child of the Godhead, I have come into this physical world to work out certain things, both in myself and in the world.

I can only do this by my realisation of my oneness with my Father-Mother, and also my oneness with all my brothers and sisters in the world.

—The Teacher