I got out my father's nylon string guitar which had only four strings because the other two had broken. The guitar was tuned perfectly to an E-tuning and I imitated what I heard coming from the wall and practiced it into the morning hours until I had it copied on my father's guitar with only what was needed; the top four strings in an 'E' tuning. Later, I developed it from the initial few notes to what it, now, is on my twelve-string guitar.
It is the eeriest, most ancient-sounding, mystical song I have ever heard. I had gotten it when I was seriously studying Xerxes and trying to determine whether I had been him or not {It Is Coming To Me, Now, That I Was His Brother.}. I felt that the song had come from God.