Knowing constancy, the mind is open. With an open mind, you will be openhearted. Being openhearted you will act royally. Being royal, you will attain the divine. Being divine, you will be at one with the Tao. Being at one with the Tao is eternal. Though the body dies, the Tao will never pass away.
So sometimes things are ahead and sometimes they are behind; Sometimes breathing is hard, sometimes it comes easily; Sometimes there is strength and sometimes weakness; Sometimes one is up and sometimes down. Therefore the sage avoids extremes, excesses, and complacency.