Is all of the Bible the inspired Word of God, and which part are we to depend on?
Yes, every word in the Book is the inspired Word of God. However, the part to depend on is the doctrines of grace given to Paul, the Apostle of the Gentiles, embedded in the Mysteries. The same unchanging God gave the Law through Moses to Israel, but later instructed Paul to take grace doctrines far hence to Gentiles and Jews.
Les explains that God gave Moses the Law at Sinai, and Moses took the Law down to Israel. Only Israel received the ramifications of the Law, although the Law certainly affected the whole human race. Then, 1500 years later, God had not changed; the same God was now dealing with a different individual. He gave Paul the doctrines of grace, which are embedded in what Paul always refers to as the Mysteries. Paul was not instructed to take these doctrines down to the nation of Israel, but to take them far hence to the Gentiles and also to the Jews. This answers what part of Scripture we are to depend on. It is all God's Word, and every word in this Book is the inspired Word of God, but God has made it plain that Paul is the Apostle of the Gentiles, as Les points to Romans chapter 11, verse 13.