Excerpt from How to Write by Richard Rhodes:
The empty page is a Spinx, blankly ferocious.
Gabriel Garcia Marquez in the introduction to his short-story collection Strange Pilgrims, calls beginning "intense":
Beginning a novel... everything must be defined in the first paragraph: structure, tone, style, rhythm, length, and sometimes even the personality of a character. All the rest is the pleasure of writing, the most intimate, solitary pleasure one can imagine,....
As for the novel, so also, mutatis mutandis, for any work of writing: the first paragraph charts a course that may lead the reader -- and will restrain the writer -- through hundreds and even thousands of pages, to the near or distant end. And first among firsts is voice: who is telling the story?
Well, who is telling the story? You, of course. Only you. .....
... Even the you who is telling your first-person personal story is you but not you, isn't it -- is one but not another of your many persona, whichever one you've selected for this particular task? It follows that voice in writing -- who is telling the story -- is always to some degree made up for the occasion, which is to say, is always fictional, even when you intend to use that voice to convey documented fact.
...
"A man cannot utter two or three sentences without disclosing to intelligent ears precisely where he stands in life and thought... " - Ralph Waldo Emerson.
Voice and its grammatical correlate, point of view, shape the frame through which your reader experiences your story. That necessary frame limits what your reader will know, of course. But its limitations cut both ways. The frame of voice limits what your reader will know because it limits what you can tell him.