In third person omniscient point of view the reader is privy to all going on, anywhere, depending upon the narrator’s movement through the structure of story and of course, reliant upon that narrator’s opinion of events and situations.
Bulgakov eases us from third person to first as he has previously described Margarita’s thoughts, but adds:
–what did she want? I do not know I have no idea. Evidently she spoke the truth when she said it was the Master she needed and not the Gothic-style house, the private garden, or the money. She loved him, she was telling the truth. (p. 186)
Bulgakov has followed the proper form of third person, switched to first, then surprises us with this:
Even I, a truthful narrator, but a detached observer nonetheless, feel my heart contract when I think of what Margarita went through the next day when she came to the Master’s house and found that he was no longer there. Fortunately, she had not as yet had a talk with her husband, who had not come home when he was supposed to. (p. 186)
Allowing the narrator a persona has added the single touch of emotion that all the drama and bizarre events did not offer, being written in a style of near-reportative fashion, a matter-of-fact totally in conflict with the surreality of the story.
Then Bulgakov moves forward, taking on and breaking the literary fourth wall:
All of this was absurd of course, since how would her staying with the Master that night have made things any different? Could she really have saved him? "Nonsense!" we would have exclaimed, but not in front of a woman who has been driven to despair. (p. 186)
With that simple technique–first asking a question of the reader, one that might also have been considered a first person pov thought instead–then the statement of what we would have exclaimed, Bulgakov has the narrator make contact with the reader and connects with him in a convivial "we." This step by step method manages to first show the reader that the narrator is indeed a person and a caring, compassionate one, but also allows that the reader is the same.
Very nicely done.