Human Redemption!
At the end of the novel readers should realize that most characters are connected to Pontius Pilate. Because of this connection, the presence of evil in humans is apparent. Pilate is forced to bear the weight of his sins for two thousand years before he is redeemed. The Master is the character most closely linked to Pilate. He wrote an entire novel about Pilate and his mannerisms, such as not being able to find peace in the moonlight, are shared with Pilate.
The Master is also linked to Yeshua Ha-Nozri. Master is a victim of Soviet society, and Yeshua is a victim of his society. Other characters linked to Yeshua are Varenukha and Freida. Varenukha throws his arms out "as though he were being crucified" and Freida "fell to the floor with her arms out, making a cross." Master, Varenukha and Freida are all tied to Yeshua and they also all achieve redemption of some sort.
Woland and his evil "crew" expliot the evil that lie deep inside the Muscovites. Although Woland punishes them for their sins, most characters are eventually forgiven. Woland is the devil. But Bulgakov decided to portray him as not entirely evil, merciful, and agreeable.
