What are the main ideas of paragraph 4, 5, and 6 of the letter from birmingham jail?

The main ideas of paragraph 4, 5, and 6 of the letter from Birmingham Jail are the following: 

First is that injustice committed in one place is injustice committed everywhere. This means that if a crime against one person is committed, then it has been committed to humanity itself. 

Secondly, it is a sad thing that the white community is simply sitting around without doing anything at all with the regards of the situation of the black community. It is one thing to talk about society's welfare but it is very different to do it. 

Lastly, there are four steps into committing into a peaceful campaigning. However, even if the said steps have been undergone through, there are still human right violations in Birmingham. This supports the main idea of the fifth paragraph. 

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