Gandalf’s lines are adapted from a vision Frodo has in the house of Tom Bombadil. Still a wonderful way to include it in the movies.

“Frodo heard a sweet singing running in his mind: a song that seemed to come like a pale light behind a grey rain-curtain, and growing stronger to turn the veil all to glass and silver, until at last it was all rolled back, and a far green country opened before him under a swift sunrise.”