First Quatrain

At first glance, "A Poison Tree" may seem straightforward, potentially misleading readers into thinking it's just another piece of children's literature. It appears to fit in with the nursery rhymes and children's verses that gained popularity and were widely published in the late eighteenth century. The most well-known collection of such verses is attributed to "Mother Goose." These verses were designed to impart moral lessons to children through memorable rhymes and engaging rhythms.

Blake starts with, "I was angry with my friend; / I told my wrath, my wrath did end." The words and emotions are simple, easily understood even by a young child. The speaker shares a personal experience: he was angry with his friend, expressed his anger, and as a result, his anger dissipated. This scenario is neatly wrapped up with the rhyme of "friend" and "end." In contrast, the speaker continues, "I was angry with my foe: / I told it not, my wrath did grow." Again, the verse appears clear and straightforward, as does the lesson: if you don't express your feelings, the negative emotions will intensify. The last two lines of the quatrain seem to affirm the wisdom of the first two: express your feelings; don't bottle them up, or things will worsen.

However, the comparison between the first and second couplets is not exact due to differing circumstances. In the first couplet, the speaker is angry with a friend; in the second, with an enemy. This distinction immediately adds complexity to the seemingly simple poem. The lines are not merely about the morality of expressing or hiding anger; they address how people categorize others as friends or foes and the distinct ways they handle these relationships. Consequently, the poem delves into the nature and consequences of anger, examining how it develops and what it can turn into.

Second Quatrain

The second quatrain, consisting of two additional rhyming couplets, feels less juvenile than the first. "And I waterd it in fears," the speaker declares, "Night & morning with my tears: / And I sunned it with smiles, / And with soft deceitful wiles." These lines depict how the speaker has nurtured and grown his anger. Unlike the first quatrain, which suggests a lesson, this one explores a process. The speaker reveals his enjoyment in his own cunning. He also begins to use metaphor, which allows one thing to represent another. The "it" in the first line of the second quatrain refers to the speaker's wrath. Instead of describing his wrath as an emotion, he treats it like a small plant. He "waterd" his anger with his tears, and, using another metaphor, he "sunned it with smiles / And with soft deceitful wiles."

Wiles are clever tricks or strategies designed to deceive. The speaker is setting a trap for his foe, enticing him with something seemingly attractive but ultimately harmful. By pretending to be friendly, the speaker's very act of friendliness fuels his anger. The fake smiles he gives his foe are like sunlight to the plant of his wrath. The friendlier the speaker appears, the more hostile he actually is, and the worse his intentions become. The innocence is gone. The speaker's actions do not reflect their true nature. He is not as he seems. By using metaphor, describing anger as a plant and hypocrisy as sunshine, the speaker portrays the duplicity of his behavior in his language, making his actions appear more appealing than they are.

Third Quatrain

What is a metaphor in the second quatrain seems to transform into reality in the third. "And it grew both day and night," the speaker states. The "it" refers to his wrath, which he has cultivated with "smiles, / And … soft deceitful wiles." In the second line of the third quatrain, however, "it" produces "an apple bright." The wrath has turned into an actual tree. Anger does not bear apples; apple trees do. The emotion has been given so much significance that it has become tangible. The fruit of the speaker's wrath is not merely like an apple on a tree; it is an apple. The speaker has made his anger appear to be something else, and it has actually transformed. He has made something deadly seem enticing and tempting to his foe.

The speaker's anger in the poem, symbolized as a tempting apple, can evoke thoughts of the apple from the forbidden Tree of Knowledge in the Garden of Eden. While that fruit appears to offer immense good, in the Judeo-Christian narrative, it actually brings about great sorrow. Similarly, the apple in "A Poison Tree" carries the same connotation. Readers might sense that Blake is hinting that in the biblical story, what is referred to as God's love is actually a form of wrath. This suggests that the God of the established Judeo-Christian religion is more a god of wrath than of love. Blake consistently conveys this belief in his longer poems. "A Poison Tree," through its use of metaphors, becomes a metaphor itself. The relationship between the angry speaker and his foe symbolizes the story of an angry god and humanity.

Fourth Quatrain

The climax of "A Poison Tree" arrives so abruptly that a break between verse paragraphs, which has marked the transition from one quatrain to the next, seems unnecessary. The first line of the final quatrain flows seamlessly from the second couplet of the third: "And my foe beheld it shine. / And he knew that it was mine. / And into my garden stole." The repeated use of "and" at the beginning of each line—a poetic device known as polysyndeton—highlights how one action directly leads to and follows another. Blake further accelerates the poem's pace through his use of the word "stole." "And into my garden stole" indicates that the foe entered the garden secretly. However, "stole" also implies theft, suggesting that the foe sneaks into the garden to commit an act of thievery under the cover of darkness. By emphasizing the word "stole," the speaker underscores the foe's guilt.

The blame largely falls on the speaker himself. As the tempter, he is the one who has set traps for his adversary and is accountable for them. The poem does not disclose whether the person referred to as the "foe" harbors any animosity or ill will toward the speaker, or if he is even aware that the speaker considers him an enemy. The poem provides no details about the "foe's" character, why the speaker regards him as an adversary, or the reasons for the speaker's anger. Furthermore, sneaking into the garden to eat the apple is not necessarily an act of hostility. It is primarily an act driven by appetite and desire, which the speaker has incited and encouraged. By using the word "stole," the speaker reveals his own excitement at leading his foe into guilt and wrongdoing, inadvertently condemning himself. The only thing Blake allows the speaker to mention about his foe is that he "stole" into the garden "when the night had veiled the pole." The polestar, or the North Star, which sailors use to navigate, is obscured. This metaphor suggests that the foe enters the garden at a time when his moral compass has been clouded by the speaker’s deceit.

The final couplet, "In the morning glad I see; / My foe outstretched beneath the tree," is more ambiguous than it initially seems. How one interprets it shapes the understanding of the entire poem. The first interpretative challenge is whether "outstretched" means dead. If it does, as the reader might believe due to the poisonous tree, the couplet reveals the speaker's depravity. It shows the speaker's delight in his enemy's downfall: In the morning, I am glad to see my foe lying dead beneath the tree. However, if "outstretched" simply means lying down—that the foe is not dead but realizes that his supposed friend is not truly a friend—then the issues of human conflict, anger, and enmity persist, as they do for everyone.

Another issue is Blake's punctuation in the penultimate, or second-to-last, line—"In the morning glad I see;"—which allows for two interpretations. There is no punctuation until the semicolon at the end. The word "glad" can describe either "morning" or "I." If "glad" describes "morning," it suggests that in the joyful, light-filled morning, as opposed to the "veiled" night, the speaker is seeing. If "glad" describes "I," it implies that in the morning, the speaker is happy to see the sight of his fallen foe. The first interpretation allows readers to see the speaker enlightened, possibly even shocked, by the fatal impact of his anger on his foe. The happy morning contrasts with the speaker's sober realization. The second interpretation reveals the effect of anger on the character of the person who harbors it, showing it is fatal to his innocent view of humanity. Blake shifts the story's focus from the Fall of humankind to the fall of God.

By turning it into a metaphor for the story of the Fall, Blake constructs the poem so that the speaker's actions, mirroring God's behavior in the Old Testament, represent God's behavior, and the speaker symbolizes God. Through his analysis and implicit condemnation of the speaker, Blake critiques the vision that created the god of the Old Testament and the attitude that this god embodies. Blake warns against this vision, attitude, and type of god, identifying him as a god of wrath and cruelty rather than one of love.