Personification is when something nonhuman is described as being human.
The personification includes “the poetry of earth is never dead” in line 1, where poetry is compared to a living thing. While the grasshopper is described physically as having a voice, resting, and being tired, the grasshopper is also described as delighting, which is a human condition. Actual grasshoppers do not feel delight. Frost is also personified because it is described as having “wrought silence,” which makes the silence seem intentional. The noise the cricket makes is also described as a song, which may also be another human trait.