The word “suffering” is discussed as follows by Liu Chuxuan: To suffer means to suffer in the mind and body. The confused people of the world make themselves suffer by coveting life and enter- ing into the road of death. Straining their minds they use their cleverness, and thus their [Real] Nature sinks into the land of punishments. One who understands the Tao makes himself suffer by training his body.
In other words, it is like shattering a rock to take out a piece of jade. Straining his willpower he forgets cleverness and therefore his [Real] Nature ascends the Nine Skies. The wise find enjoyment in the midst of suffering. The foolish suffer in the midst of enjoyment. For the wise, bitterness ends and sweetness arrives. For the foolish, enjoyment climaxes and then they are sad.