Worldly Pleasure vs. Eternal Freedom
The issue brought up by the parallels to Faust is the common one regarding a "deal with the devil." Often the main character, depressed by his life, agrees to serve the Devil in the afterlife in exchange for earthly power and pleasure. The problem, as these characters figure out, is that worldly pleasure is only temporary and never completely satisfactory - they certainly have gotten the worse end of the bargain. This theme is especially apparent in That Old Black Magic when Shorty expresses his disillusionment with boxing glory and his anxiety about Shadow's deal.
Familial Bonds
Shorty has a strong relationship with his sister, Angie, who encourages him and helps him through his difficulties. She reminds him of the good aspects of his situation, and she isn't afraid to stand up to Shadow on Shorty's behalf for what she believes is right. Their relationship is bolstered by their joint acting in Shorty's makeshift rendition of Goethe's Faust, although it involves an unusual (and perhaps alarming) amount of romantic intimacy between them.
Consequences for One's Actions
The theme of the inevitability of consequences is evident throughout the play. Shorty makes a deal with Shadow, and the consequences of this arrangement are obvious: Shorty becomes powerful and famous, but loses his soul. Later, when he stands up to Shadow and refuses to live by his rules any more, there are also consequences: because of his rebellion, Shadow forces him to live inside the ring of his own mind, little more than a shadow himself as he is forced to live out Shadow's will.
