Authority of Scripture

Scripture (the 66 books of the Bible) is the first authority in all things concerning history, morality, and doctrine.  All other sources are secondary to Scripture and must be tested against Scripture.  That which contradicts Scripture is to be exposed [Ephesians 5:11] and rejected.  Secondary sources may be used to give historical context that Scripture leaves out or as complementary to Scripture if they do not contradict Scripture.  The use of such sources however, either by Scripture itself or by those teaching from Scripture, does not make said sources equal to Scripture.

Not all Scripture has the same authority.  Neither is all Scripture the "word of God", though it is all inspired by God [2 Timothy 3:16].  That which is the word of God is inerrant in everything that it says, for God knows everything and wants us to know the truth.  Torah (Genesis-Deuteronomy) is the Law of God and contains everything that God commanded Moses to write in it [Exodus 24:4].  What it says is exactly what God commanded it to say.  It sets the standard of right and wrong and is the foundation of the rest of Scripture.  Anything that is contrary to Torah is false doctrine.

The writings of the prophets record everything that God commanded the prophets to speak.  A prophet is tested against Torah first, then against his/her own prophecies.  Any prophet who claims to be speaking in the name of God must have a 100% success rate or that person is a false prophet.  If even one prophesy fails, then the prophet is a false prophet.  If the prophet should speak something that is contrary to Torah, that prophet is a false prophet.  After a prophet has passed all of the tests, then any prophet that comes afterwards that speaks what is contrary to that prophet is a false prophet.  Anything contrary to the writings of the prophets is false doctrine.  Revelation is considered prophesy, under the rules laid out for prophesy, with anything after it also being subjected to testing against it.

The Gospels and Acts are first-hand historical accounts of the life, death, and resurrection of Yeshua (Jesus) the Messiah and the events that came afterwards.  These accounts were given by men who were compelled by their faith to give a factually-correct account of the events that they witnessed.  These accounts record the fulfillment of every prophesy concerning the Messiah as well as the things that Jesus taught.  These accounts (and even Jesus) are tested against Torah and the prophets.  All of Jesus' teachings come from God the Father.

The epistles are letters of instruction and encouragement to various congregations or individuals living in the first century.  They are every bit as applicable today as they were 2,000 years ago.  That being said, they still must be in line with Torah and the prophets, as well as being inline with the teachings of Jesus.

The historical writings of the "Old Testament" give the most accurate accounts of the events in the middle-eastern region from about 1,500 B.C.E. to about 400 B.C.E.  These writings are still tested against Torah, but also record the various prophecies coming true (given that they were fulfilled before these documents were produced).  Books like Psalms and Lamentations contain songs that were written by the author's own free will and include songs of praise, prayer, repentance, wisdom, instruction, and other types of songs.  Proverbs and Ecclesiastes were written specifically as books of wisdom.