The personification in A Poison Tree exists both as a means by which the poem's metaphors are revealed, supported, and as a way for Blake to project the greater illustration of wrath. The wrath the speaker feels is not directly personified as a tree, but as something that grows slowly and bears fruit. In the opening stanza the speaker states, “My wrath did grow.” The speaker later describes the living nature of the wrath as one which, “grew both day and night,” and, “bore an apple bright.” This comparison by personification of wrath to a tree illustrates the speaker's idea that, like the slow and steady growth of a tree, anger and wrath gradually accumulate and form just as deadly as a poisoned tree.
To understand the metaphorical theme of the poem, I believe you have to examine the title, A Poison Tree. This hints to the reader that some type of metaphor will be dominant throughout the poem. In the second stanza, Blake uses several metaphors that reflect the growing and nurturing of a tree which compare to the feeding of hate and vanity explored by the speaker. The verses, “And I watered it …with my tears” show how the tears of life lead the deadly object that we know as A Poison Tree. The speaker goes on to say, “And I sunned it with smiles” describing not only false intentions, but the process of “sunning”, giving nutrients to a plant so that it may not only grow