The statement which best restates the main idea of the quotation is the following one:
It’s not good to criticize others because we don’t know what they face in life.
People generally criticize everybody, especially someone they do not like for some reason. However, doing so is wrong, since we don't know why a person behaves in this or in that way. As Nietzsche said, one cannot be blamed for being who he or she is; every single individual is the result of a series of circumstances. It does not mean we are allowed to do whatever we feel like without measuring the effect it might have on others; it simply tells us that whoever we criticize, for whatever reasons, does certain things and acts in certain ways due to the large number of circumstances which that specific individual had to experience throughout life.