A green bird darting in the night.
Will you be able to see it?
Will you be able to catch it?
Cling to Tao like a shadow.
Move without a shadow.
Times of oppression and adversity cannot last forever. How is the transition made to new and better situations? In the midst of great difficulty, a tiny opportunity will open, if only by chance. You must be sharp enough to discern it, quick enough to catch it, and determined enough to do something with it. If you let it pass, you will be filled with regrets.
Stick to Tao like a shadow. Wherever it goes, you go. As soon as it throws something your way, catch it by sheer reflex. It is like the bird : If you try to catch it, you will miss. If you are always with it, moving at its speed, as much a part of it as its own shadow, then it is easy to seize it.
When you act, however, you in turn must have no shadow. In other words, what you do must leave no messiness, no leftover consequences, nothing that will haunt you later. That is one of the ways in which you avoid creating more bad situations for yourself : Your every movement is traceless.