Perhaps I should expound on what I posted. When I was young and started reading the Bible, I have to admit, I didn't notice who was being spoken to. In fact, I attended a Non-Denominational, Mid-Acts Dispensational Church since I was twelve years old. However, for a number of years, I don't remember them speaking on the topic, therefore, I wasn't actually privy to what I call: The MAD Tool." I didn't discover the "Tool" until several years later. In reality, Mid-Acts Dispensationalism IS part of the Gospel. It is intertwined within the very fibers of the Gospel. As you mentioned, There are times when the each book states at the beginning, who is being spoken to. If it doesn't mention at the beginning, one can more or less ascertain that information in the text itself as you continue to read and study it. Personally, I don't believe one can separate Mid-Acts Dispensationalism from The Scriptures. However, I do believe one can be a member of the Body of Christ without being enlightened about Mid-Acts Dispensationalism. Posters on this forum seem to be adverse to the word "MAD", that's why I'm writing it out in its entirety, rather than using the abbreviation.
I believe the word "MAD" has gotten a bad rap around TOL. Posters don't seem to understand Mid-Acts Dispensationalism, therefore, they mistrust what's being taught, regarding it. As I stated early on, I attended a Mid-Acts Dispensationalist Church and didn't understand it for several years. Once you understand the "MAD Doctrine" it opens the window of your mind/heart to a fresh breeze of truth and understanding. It takes away the shroud of any confusion and so-called contradictions, one may encounter.