St. Paul makes three statements arguing for the truth of Tradition: "So then, brethren, stand firm and hold to the traditions which were taught, whether by word or by letter from us." [2 Thess. 2:15] "Now we command you, brethren, in the name of our Lord Jesus Christ, that you keep aloof from every brother who leads an unruly life and not according to the tradition which you received from us." [2 Thess 3:6] "Now I praise you because you remember me in everything, and hold firmly to the traditions, just as I delivered them to you." [1Cor 11:2] Now, a Protestant argument goes like this: "The Bible does not tell us that there is a pool of Tradition which exists separately from the Bible. Nor does the Bible give to this alleged tradition the weight of added certainty of the revelation of God that is necessary for our Salvation or Sanctification or Service. When things of substance are spoken of in the Bible, the apostles appealed to the Written Word and not to an alleged outside source of tradition." [www.sxws.com]. First of all this argument is logically in error because Tradition, by its very nature, consists of a pool of beliefs. There is no need for the Bible to say there is a pool of tradition; it is self evident. Secondly, whenever statements are made about the Apostles appealing to Scripture, they are always appealing to the Old Testament. The New Testament had not yet been written. And the Jews had many traditions not found in the Old Testament. Finally, all arguments against Sacred Tradition fall flat in the face of Timothy 3:15.
They're being exhorted to stand firm, and hold to traditional teaching in scripture, here. It's not in any way a rationale for the Roman Catholic Church acquiring later traditions that are at variance with scripture.
14But you, remain faithful to what you have learned and believed, because you know from whom you learned it,i
15and that from infancy you have known [the] sacred scriptures, which are capable of giving you wisdom for salvation through faith in Christ Jesus.j