We build in thought the conditions that will later come into manifestation on the physical plane.
What we experience is our own concept of things. That is why no two people see quite the same world, and why, in many cases, different people see such different worlds. To put it another way, we make our own world by the way in which we think; for we really do live in a world of our own thoughts.
Whatever you experience in your life is really but the outpicturing of your own thoughts and beliefs. Now, you can change these thoughts and beliefs, and then the outer picture must change too. The outer picture cannot change until you change your thought.
We affirm the harmony that we seek in order to provide the subconscious with a blue print of the work to be done.