Symbolism, Imagery, Allegory
In one of his key speeches, Black explains what everlasting life is. White's just denounced the idea that you don't have to die at some point, but Black responds by explaining what he really means:
BLACK: …That ain't what he said. He said you could have life everlastin. Life. Have it today. Hold it in your hand. That you could see it. It gives off a light. It's got a little weight to it. Not much. Warm to the touch. Just a little. And it's forever. And you can have it. Now. Today. But you don't want it. You don't want it cause to get it you got to let you brother off the hook. (78)
In other words, eternal life starts in this life. Before, when Black believed he was still in charge and was preoccupied with selfish aims and desires, he says it only got him "Death in life." But real life starts when you put all that away, and try to relate to the common humanity or soul in people—when you recognize yourself as an equal part of humanity, as part of collective existence instead of just your individual experiences. White's not about this, though, instead preferring his assessment of the purposelessness of life… that he's come to all by himself.