In the first paragraph, MLK addresses the clergyman's words concerning the timing of the movement being "unwise and untimely", stating that he didn't have to take the time to answer the clergyman's questions, but because he respects them, he will answer their letter.
King's goal in issuing his "letter from a Birmingham jail" was to address criticisms directed against him by individuals who unarguably should have known better. The teachings of Jesus, he repeated, provided for the nonviolent activities that were solely intended to correct injustices.
For the main reason that "it promoted sacrifice for the common good." the speech was commonly read during the Cultural Revolution. This speech was the primary political propaganda of Mao Zedong as a slogan during the dark times of the Chinese cultural history.
