In the story "Sonny's Blues," Sonny says...
...what heroin feels like sometimes-when it's in your veins. It makes you feel sort of warm and cool at the same time. And distant. And- and sure." He sipped his beer, very deliberately not looking at me. I watched his face. "It makes you feel-in control. Sometimes you've got to have that feeling."
When Sonny speaks, he refers to suffering in life. And as he tries to describe it to his brother, he says that everyone suffers and everyone tries to find the best way to deal with it. While the narrator believes that the drug will kill the user and that somehow that is the user's intent, what Sonny says is that he only wants to survive and he sees the heroin as his lifeline.
Listening to Sonny, the reader learns that other users he knows all need the drug, but handle the addiction in different ways: accepting that it's a part of life, or denying it altogether.
Perhaps the control Sonny feels keeps the fear at bay: the fear of suffering—the same fear the adults saw as the evening arrived on Sunday afternoons in the living room. The children did not understand it, and perhaps Sonny does not really understand it either even though he is no longer a child. Perhaps the heroin allows him to avoid fear, and maintain a distance from the suffering that life brings with it.
Sonny's reasons for using all seems to revolve around suffering and surviving. Sonny's redemption is seen when he finds his way in the music at the club, but the true sadness comes from Sonny's childhood friend who the narrator meets leaving school as the story begins: telling the reader with chilling clarity that no matter what may happen while Sonny is in jail—he may get cleaned up—he will never be free of the addiction.
And so the terrible irony is clear: Sonny takes the heroin so that he can feel like he is in control. The truth is that the control he feels is really a lie, an illusion. Sonny does not have the control: the drug does. If Sonny's friend is correct, the relationship between Sonny and the drug will never change.
After Sonny has been living with the narrator, the narrator watches his brother who stands on the edge of the crowd that listens to the music of a street revival, music that seems "to soothe a poison out of them." Sonny then walks home with his musical walk. When he enters the house, the brothers watch together out the window.
"When she was singing before," said Sonny, abruptly, "her voice reminded me for a minute of what heroin feels like sometimes...warm and cool...it makes you feel--in control. Sometimes you've got to have that feeling."
To endure Sonny has taken heroin: "It's to stand it, to be able to make it at all. On any level." Sonny refers to what his mother would talk about--the "darkness" of life outside their home. He tells the narrator that their suffering as residents of Harlem in the "killing streets" with all "that hatred and misery and love" is what has brought him to heroin:
"No, there's no way not to suffer. But you try all kinds of ways to keep from drowning in it, to keep on top of it, and to make it seem--like you....I was all by myself at the bottom of something."
Sonny also reveals to his brother that he sometimes felt the most creative on heroin as then "it just came out of me, it was there." He confesses that he had wanted to leave Harlem so badly to get away from drugs. But, of course, he did not escape because he did not find his way out of the suffering. That is, until he plays in the jazz club with his brother watching. Then, the symbol of suffering and trouble appears above his head--"the very cup of trembling," a cup that the brother also recognizes and they together find their meaning in the blues.