The central theme of The Potting Shed is that of rebirth. The potting shed is the symbolic location of James’s resurrection from the dead. It is a place filled with bulbs and packets of seeds, emblems of new life. Ironically, the sterile and oppressive godless humanism of his father drove the young James to take his own life in this symbolic shed and to rise again, like Lazarus, a committed Christian.

Another theme embodied in the play derives from Graham Greene’s obsessive concern with the devastation of childhood innocence. Old Mr. Callifer’s lifelong dedication to obliterating belief in the supernatural undermined James’s simple childhood faith and led him to his hopeless act of suicide. Callifer’s books, The Cosmic Fallacy and He Was a Man (which argues that Jesus was a Palestinian religious leader but not God), with their sterile reasoning, are contrasted with the fertile seeds and bulbs of the potting shed and the simple faith of Mrs. Potter. The attempt by a sophisticated, intellectual adult to corrupt innocence is thus overcome by the force of a simple, instinctive faith in natural and spiritual rebirth.

It may seem somewhat contrived, however, for a priest to offer to sacrifice his faith to save his nephew’s life. The bargain almost seems a parody of putting God on the spot rather than the plea of a desperate man who deeply loves his nephew. Furthermore, the significance of the miracle is attenuated by the fact that James’s life is not spiritually renewed until many years later, when he finally learns from his uncle what happened in the potting shed.

The dramatic occurrence in the shed, however, has a powerful impact on James’s family, even though he is unaware of that. Even as his father’s rationalism ruined his childhood, James’s resurrection has undermined his family’s certainty that life has no supernatural bearings. His rebirth, in effect, has destroyed his father’s life work of rooting out faith in God.