Indeed, the word "mysticism" - like the word "myth" - has managed to pick up some unpleasant intension - probably because both words are often used to describe malevolent or bizarre occults.
But of a truth, the word "mysticism" merely means divine knowledge, or more specifically, direct Spiritual knowledge - thus in Christian theology, the indwelling Spirit is called Christian mysticism. We have the mind of Christ.
Likewise a "myth" is secret speech, a lesson or teaching in story form. By using allegories, metaphors and other literary devices myths convey understanding where more direct language fails. Parables are like short myths. The "lesson" conveyed by a myth may be insignificant or profound.
I know.. I just don't like it(the word)... I'm not real hot on the word God either...LoooL.. Seems so impersonal.. I use them both but they both seem be missing something, I prefer other words.. talking about you know who.. d;-) There are other words that crawl my nape too.. Like saying orientated instead of oriented... Yeah I'm a little nutz..