Please show an infallible source that shows that the traditions taught by the Catholic Church are the same as traditions the apostles were talking about.
"Hold fast to the traditions we have handed on to you, either by word of mouth or by letter." --St. Paul
Paul divides Sacred Tradition into Oral Tradition and Written Tradition (Scripture).
By definition, Oral Tradition isn't written down.
The Sacred Oral Tradition of the Church is the infallible authority.
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On occasion, Sacred Tradition is formally declared and defined by the Church. This usually happens when it is challenged by a heretic.
Such was the case with the doctrine of the Trinity, which was formally defined in response to the spread of the Arian heresy.
Similarly, although the canon of Scripture had been defined by several local Church Councils in the fourth century, the Traditional canon of Scripture wasn't universally, formally defined until Trent, in response to Luther's removal of several books from the canon.