Where does Su Shi's poem "A misty rain makes a lifetime" come from?

On the one hand, Su Shi is a loyal and patriotic person, eager to learn and be an official, full of ambition and abiding by Confucianism. However, it should be noted that the main image left by Su Dongpo to future generations is not this side, but only the other side of him. This other aspect is the key to why Su Shi is Su Shi. Su Shi never retired in his life, nor did he really "return to the field", but the sense of emptiness in life expressed in his poems is deeper and heavier than any empty or actual "retirement", "return to the field" and "seclusion" of his predecessors. Because the state of mind of "retreat" expressed in Su Shi's poems is not only a retreat to politics, but also a retreat to society; It is not the fear and sorrow of political killing, but the suspicion, boredom and desire and abandonment of the fundamental problem of the purpose and significance of all the troubles in life and the world. This is of course a deeper layer than the former. It is possible to retire politically, but it is actually impossible to retire from society. This has become a kind of boredom and sentimentality of the whole life that cannot be relieved and needs to be relieved.

Poetry: If you don't listen to the sound of beating leaves in the forest, why don't you sing walking bamboo straw sandals more flexibly than riding a horse? What's terrible? A raincoat and hemp fiber, despite the wind and rain, still live my life.