Deal with a man as he deals with you.

Don't contradict, don't do what you don't want others to do. What you don't like is that you can't impose it on others. What you care about is kindness, which is a manifestation of self-conduct. Deal with a man as he deals with you, that is, deal with a man as he deals with you. It is often an attitude towards people with bad moral character. The context and object of the two sentences are still different.