Didascalicon, Book V: the senses of Scripture and the three kinds of readers
Chapter I. A forewarning about certain properties of sacred Scripture
It ought not to be burdensome to the studious reader that we treat so variously and manifoldly the number and order and names of the divine books, because it often happens that these least things, if unknown, obscure the knowledge of great and useful matters. Therefore let the reader once for all be set free, so that, these as it were certain bars having been unlocked at the first approach, he may then run the intended road with free step, and not need to seek new rudiments in each book. These matters, then, being dispatched, we shall afterwards treat the rest that will seem to avail for the work proposed.