Revelation: a usually secret or surprising fact that is made known

Source: http://www.merriam-webster.com/dictionary/revelation

“While living at 19 Willoughby I learned what kind of write, what kind of lover and even what kind of son I was. But the most surpriseing revelation that I was a mentor and, like my mother, a kind of teacher.”

Nelson George uses the revelation to show the reader that after moving to Fort Greene, he realizes what kind of person he was after performing.