The poem is about the dangers of suppressed anger. In the first stanza, the speaker's anger dissipates when talking to a friend, but grows when kept quiet about anger towards an enemy. In the second stanza, the speaker's anger flourishes in secret. In the third stanza, the anger bears poisonous fruit ("an apple bright") that deceives the enemy. In the fourth stanza, the enemy eats the apple in the night and is poisoned, satisfying the speaker. The poem warns that suppressing anger only makes it grow and can have destructive consequences.