| Quote #1
Helen, thy beauty is to me
These lines are most likely a reference to the Roman poet Catullus. The speaker compares himself to a poet who was and is nothing short of a big deal in the history of poetry. It sounds like he is making himself seem important as a poet.
| Quote #2
Thy hyacinth hair, thy classic face,
Helen's features resemble a famous work of art. Her hair is just the right color and length, and her face is a classic. This foreshadows the final stanza, where the speaker compares Helen to a statue.
| Quote #3
Lo, in yon brilliant window-niche
The speaker says Helen is "statue-like." This phrase suggests that she is beautiful, but also dead. A statue is a piece of stone. It isn't "alive" (it doesn't move or anything like that). Perhaps the speaker is implying that his idea of Helen is just an idea, a fantasy.