text: Poisoning appears in many of Blake's poems. The poisoner of "A Poison Tree" is similar to Blake's Jehovah, Urizen, Satan, and Newton. Through poisoning an individual, the victim ingests part of the poisoner, as food, through reading, or other actions, as an inversion on the Eucharist. Through ingestion, the poisoned sense of reason of the poisoner is forced onto the poisoned. Thus, the death of the poisoned can be interpreted as a replacement of the poisoned's individuality. The world of the poem is one where dominance is key, and there is no reciprocal interaction between individuals because of a lack of trust.
  The poem, like others in Songs of Experience, reflects a uniquely Christian sense of alienation. As such, "A Poison Tree" appears to play-off the Christian idea of self-denial, and it is possible that Blake is relying on Emanuel Swedenborg's theme of piety concealing malice, which ultimately alienates the individual from their true identity and evil no longer appears to be evil. Blake's poem differs from Swedenborg's theory by containing an uncontrollable progression through actions that lead to the conclusion. The final murder is beyond the control of the narrator, and the poem reflects this by switching from past to the present tense. The poem's theme of duplicity and the inevitable conclusion is similar to the anonymous poem "There was a man of double deed."