Swami Vivekananda

Take up one idea. Make that one idea your life - think of it, dream of it, live on that idea. Let the brain, muscles, nerves, every part of your body, be full of that idea, and just leave every other idea alone. This is the way to success.

The mind itself is of the form of all, i.e., of soul, God and world; when it becomes of the form of the Self through knowledge, there is release, which is of the nature of Brahman: this is the teaching.