You have yet to find me a place that says scripture only in the bible. And that is because it isn't there. And of course post 82 by sock, and my post 107 are questions that are still unanswered. The truth is that before scripture was compiled the church was already functioning. Paul's letters were sent to settle disputes in the church, not as lesson plans.
And as Augustine put it, ‘I would not believe in the Gospels were it not for the authority of the Catholic Church’ (Against the Letter of Mani Called "The Foundation" 5:6).