I am always intrigued to know the origin of words, phrases, proverbs and so on, if only so that I don’t use them anachronistically in my books. It’s not always possible, of course, because some things are just too engrained in the English language, and sticking to the correct English for, say, the 15th century, would make for an impossible book for me to write, or for a reader to get to fully enjoy. Unless they have degrees in such things! That’s my opinion anyway.
Some of the phrases contained in the following link were known to me as being from Shakespeare, but I certainly didn’t know all of them. It’s an interesting subject.
However, it often happens that an author—or an entry in a dictionary that is given a specific date—turns out to have merely recorded something that was in circulation anyway. I’m not saying this is necessarily the case where Shakespeare is concerned, but I have to wonder if he is the source of all the phrases accorded to him. In my writing career I try to stick to the proper dates, but have discovered before now that, e.g. Merriam-Webster, isn’t always spot-on. A lot of authors use MW, indeed it was specified by one of my publishers. But I’ve found words/phrases to have been extant at a far earlier date than MW gives in its hallowed pages. I informed them on one occasion, having found sources up to a century earlier, but didn’t get an acknowledgement. I haven’t tried since. So the incorrect date remains in place. Please don’t ask me to identify the word in question, because I can’t remember. It was years and years ago.