What's the meaning of the title : The Master and Margarita?

I've mentioned in recent posts several books that Mikhail Bulgakov's "The Master and Margarita" reminds me of, and here's another one - though I doubt Bulgakov would have read it but it does seem like a possible influence: Melville's The Confidence Man - another novel about a trickster who appears in many guises and causes havoc, a very difficult novel - much like The M&M - which, as it moves toward the end of Book I, goes back to another eye-witness account of the crucifixion, this time as seen by the disciple Matthew - what is this all about? What Bulgakov just trying to provoke the Soviet censers? He must have known this book would never be published in his lifetime - if it were, it would be been the end of his life, in any case. As everyone moves inexorably toward confinement in Stravinsky’s mental hospital – I have to wonder, what’s the significance of the title? The Master seems to be the writer whom we’d met in the hospital, a man at the end of his wits because he has been unable to publish his novel about Pontius Pilate (a version of B. himself, obviously), but who is Margarita? No doubt she will appear in some guise in Part II – and she is evidently some reference to Faust’s enticing beloved, but how she fits into the scheme of The M&M, however loose that scheme may be, is completely beyond me at this point.