And I sunned it with smiles, And with soft deceitful wiles. (7-8)
The rhyme on "smiles" and "wiles" emphasizes the speaker's deception; "smiles" are supposed to indicate happiness, or pleasure, or friendship—in short, any number of positive things. The fact that "smiles" is paired with "wiles" illustrates the lack of any genuine emotion on the speaker's part.
And it grew both day and night, Till it bore an apple bright. And my foe beheld it shine. (9-11)
The apple is deceptively "bright" and "shiny." We know it is poisonous and that nothing good can come from it. The poem suggests that anger can make things appear to be what they are not. In a sense, anger releases a silent killer, something that is in reality incredibly dangerous, not the least because it is so alluring.
And into my garden stole When the night had veiled the pole; (13-14)
It appears the "foe" is deceitful as well, as he sneaks into the speaker's garden at night. Of course, for his part, the foe is deceived by the allure of the apple. Deception seems to infect, and affect, everyone in the poem.