The Holy Spirit guided the Catholic Church to recognize and determine the canon of the New and Old Testaments in the year 382 at the Council of Rome, under Pope Damasus I. This decision was ratified again at the councils of Hippo (393) and Carthage (397 and 419). You, my friend, accept exactly the same books of the New Testament that Pope Damasus decreed were canonical, and no others.
The question you have to ask yourself is this: Where did we get the Bible? Until you can give a satisfactory answer, you arent in much of a position to rely on the authority of Scripture or to claim that you can be certain that you know how to accurately interpret it.