The tree in Blake’s poem can be interpreted as an allusion to the Tree of the Knowledge of Good and Evil in the Bible. Defying God's command, Adam and Eve eat from the tree, and in return, God expels them from the Garden of Eden.

How does this allusion affect the poem's mood?

It fills the poem's mood with hope and joy.

It helps create a mood of sin, guilt, and mystery.

It generates a hushed, deeply religious mood.

It develops a mood of wisdom rooted in experience.