Acts 17:11King James Version (KJV)
11 These were more noble than those in Thessalonica, in that they received the word with all readiness of mind, and searched the scriptures daily, whether those things were so.
All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness:
http://www.kingjamesbibleonline.org/2-Timothy-Chapter-3/
What does that quote about all scripture (which when written meant the Old Testament only) mean to you?
Does “profitable” mean “Both necessary and sufficient” in any dictionary you have ever used?
Who decided that the writings of Matthew, Mark, Luke, John, Paul, and Peter were scripture? Was that decided before, or after, Acts was written?
When to was decided that what we now call the New Testament WAS scripture, where did the authority come from to declare and to limit what was included?