Where does scripture say that we must only use scripture as authoritative? As you can see, I'm not that well-versed, so please quote me the scripture where that is said. I really need to brush up on my Bible study. Your quote may help me to get motivated.
2 Thessalonians 3:6 (New American Standard Bible)
6Now we command you, brethren, in the name of our Lord Jesus Christ, that you keep away from every brother who leads an unruly life and not according to the tradition which you received from us.
Rather than teach a Bible class here, I would direct you to II Timothy 2:15. You will benefit more by being the one who does the work.
ampu