This has to be the top, number 1, beyond all doubt, most abused passage that the RCC uses to justify its claims to the so-called "oral tradition." It is utterly disguisting the ignorance propagated by the RCC.
My friend, if you will look at the context, you will see the complete lack of exegetical ability of the RCC. Since you and all other Catholics up here on FR constantly hammer this verse ... I am going to take the time to post the entire chapter in context ... and I pray that God will open your eyes to see the truth ... that it has NOTHING to do with what you claim.
1 Now we request you, brethren, with regard to the coming of our Lord Jesus Christ and our gathering together to Him,
2 that you not be quickly shaken from your composure or be disturbed either by a spirit or a message or a letter as if from us, to the effect that the day of the Lord has come.
3 Let no one in any way deceive you, for it will not come unless the apostasy comes first, and the man of lawlessness is revealed, the son of destruction,
4 who opposes and exalts himself above every so-called god or object of worship, so that he takes his seat in the temple of God, displaying himself as being God.
5 Do you not remember that while I was still with you, I was telling you these things?
6 And you know what restrains him now, so that in his time he will be revealed.
7 For the mystery of lawlessness is already at work; only he who now restrains will do so until he is taken out of the way.
8 Then that lawless one will be revealed whom the Lord will slay with the breath of His mouth and bring to an end by the appearance of His coming;
9 that is, the one whose coming is in accord with the activity of Satan, with all power and signs and false wonders,
10 and with all the deception of wickedness for those who perish, because they did not receive the love of the truth so as to be saved.
11 For this reason God will send upon them a deluding influence so that they will believe what is false,
12 in order that they all may be judged who did not believe the truth, but took pleasure in wickedness.
13 But we should always give thanks to God for you, brethren beloved by the Lord, because God has chosen you from the beginning for salvation through sanctification by the Spirit and faith in the truth.
14 It was for this He called you through our gospel, that you may gain the glory of our Lord Jesus Christ.
15 So then, brethren, stand firm and hold to the traditions which you were taught, whether by word of mouth or by letter from us.
So now the analysis ...
Vs 1-2: Paul instructs the Thessalonians "not to be shaken" or "disturbed" believing that the Day of the Lord has already come. He says don't let a spirit or a letter or anything deceive you concerning this. It is conceivable that those who are spreading this false doctrine have forged a letter and claimed it was from Paul.
Vs. 3-4: He begins to remind them of the correct precursors to the Day of the Lord, those being the apostasy, man of lawlessness, etc. etc.
Vs. 5: Paul reminds them that he already taught them these things when he was there in Thessalonica!
Vs. 6-12: Paul continues to list out the events surrounding the Day of the Lord and the particular persons who will be involved in those events; namely, the man of lawlessness, the Lord Jesus Christ, and unbelievers.
Vs. 13-14 He reminds them that they have been chosen for salvation, they were called by the gospel, and that they are going to glory.
This ... THIS is the context of the passage that the RCC butchers time and time again.
In this context, what does verse 15 say?
So then, brethren, stand firm and hold to the traditions which you were taught, whether by word of mouth or by letter from us.
Vs. 15: So then, because of this, because I have already taught you this, and I have just reminded you of what I taught you before ... because of this ... "stand firm" (not be shaken!) ... and hold to the traditions ... WHAT traditions? ... The traditions concerning the Day of the Lord, the teachings he just regurgitated to them concerning the Day of the Lord ... those things "which you were taught" ... when did he teach those things ... WHEN HE WAS THERE ! "Whether by word of mouth" (when he was there!) ... or by letter (1st and 2nd Thessalonians!) ... hold fast to those teachings.
THIS is the passage in context. It has absolutely nothing to do with any so-called "apostolic traditions."
There is nothing left to say than to call you to repentance for maintaining and spreading false doctrine.
My vote is for 2 Timothy 3:16.