The way of Heaven and Earth may be completely declared in one sentence: They are without any doubleness, and so they produce things in a manner that is unfathomable.
What Heaven has conferred is called The Nature; an accordance with this nature is called The Path of duty; the regulation of this path is called Instruction. The path may not be left for an instant. If it could be left, it would not be the path.
The Master said, If out of the three hundred songs I had to take one phrase to cover all my teachings, I would say 'Let there be no evil in your thoughts.'