I have always thought of the word "rid" to being synonymous with the word "toss" or "throw away". For example, "I got rid of some old stuff". But rid is actually means to "free ourselves of unwanted people or things". When we understand the true meaning of "rid", we can truly understand why God wants us to "get rid" of things that harm us, because they are not useful.
Lord, help me to free myself of those things in my life that I think are helpful but are actually harmful and therefore, I shouldn't want them.