This has a Biblical origin. It can be found in various passages in the Old Testament and New Testament John 8:52-55). It eventually came to mean a convenant or promise that would be considered heartfelt and lasting. (IMHO)
I was told it has Welsh, English and Scottish origins. I at first thought it was Hebrew or derivative of a Hebrew phrase or word, but I guess not.
The Bible
stop
from joey in friends
latin
This phrase means that one is honest, trustworthy, that they can keep a promise, their "word is as good as gold."
The phrase "mug's game" means something that is a futile endeavor. It comes from the Scandinavian word mugge, which is slang for an idiot.
1820-30
from girls ...to hissy...
in concord and lexington.
facebook entry
Yes, the word "bolshy" does originate from the "bolsheviks".