What is the purpose of the stanza?

example: The purpose of this stanza is to develop a general time and place - setting - for 'The Raven'. In this stanza, the month is identified as a cold one and an unsavory one. Additionally, a fire is dying as a person seeks to grieve through reading a book. He is grieving over the loss of his love, Lenore. At this point, because it's so early in the narrative poem, no real tension - stress - has been developed, but we can begin to wonder over how the character will cope with the loss of his love. After all, he does refer to her as a "rare and radiant" maiden.

Deep into that darkness peering, long I stood there wondering, fearing,
Doubting, dreaming dreams no mortal ever dared to dream before;
But the silence was unbroken, and the stillness gave no token,
And the only word there spoken was the whispered word, “Lenore?”
This I whispered, and an echo murmured back the word, “Lenore!”—
Merely this and nothing more.

The purpose of this stanza is to build suspense and establish a sense of mystery in the poem. The protagonist is described as standing in darkness, peering into it and feeling a combination of wonder, fear, and doubt. The silence and stillness of the scene add to the atmosphere of anticipation. The only word spoken is the protagonist's whisper of "Lenore," which is echoed back to them. This creates intrigue and raises questions about who or what Lenore is and what significance she holds in the story.