Anatomy of the sentence:
Bad men need nothing more to compass their ends, than that good men should look on and do nothing
I know this is the origin of "all that is necessary for evil to triumph, is that good men do nothing", and I know exactly what the latter sentence means. The thing is I don't know how it is relate with the sentence in the title. Can anyone decompose and explain it, especially for the phrase "compass their ends" and the structure "A need nothing more to do than B should do"? Just a simple explanation would be appreciated.