Board Thread:Character Discussion/@comment-3407907-20150330161804/@comment-25926288-20150330164924

It was explained in the episode (to answer you question) that it is a job and the Sorcerer "chooses" or at least punishes the author if that person goes out of line. I think it's a job that you are given (or asked to take) after the previous one dies. The peddler seems to age, so I don't think he's anything other than an ordinary man given a magic quill over the book.

What we know about the Peddler is that he doesn't seem to try to mess up people's lives (Regina's or Rumple's); he just wants to make the stories more interesting.

The Apprentice is simply the hand of the Sorcerer (or the conduit of his power). The Apprentice says you made me do that. Then he goes on saying that the Peddler deceived us. So, the Sorcerer seems to be outside of the control of the book and quill, while the Apprentice is not.