I know you are trying to defend the RCC tradition, and I know what they are attempting to say, but this interpretation is not the way Paul uses it because Paul says it has been revealed. It is not a mystery to the believer.
But it would be ridiculous to assert that the CC doesn't want that light to shine brighter; shes always proclaimed and taught the truth that gives man hope in a lost and dying world and sets him free (fhansen)
The Catholic church teaches that they are the priests and mediators to God. That is not truth. We are saved by grace unto works, and certainly do not need a priest or a church to save us, yet that is what the CC has taught for 15 centuries. And they have put Christians to death, and burned books for centuries.
Musterion: a mystery, secret, of which initiation is necessary; in the NT: the counsels of God, once hidden but now revealed in the Gospel or some fact thereof; the Christian revelation generally; particular truths or details of the Christian revelation (Strongs)
Musterion: Mystery - is not something unknowable. Rather, it is what can only be known through revelation, i.e. because God reveals it. (Strongs)
So we agree, it is unknown,
until it is revealed. If you are in
The Church it is because you
know, and have
believed Gods revelation. So why does the CC use the word mystery, and call the sacraments and the Gospel a mystery
within their churches? If your in the Church, you are (should be) a believer. It is not biblical, for a believer, to call the Gospel a mystery.
It is though, a bit revealing! Maybe because for the leaders of the CC, the Gospel has not been revealed. Otherwise they would understand the Gospel. The Gospel has been revealed,
perhaps the CC just does not understand it:
At that season Jesus answered and said, I thank thee, O Father, Lord of heaven and earth, that thou didst hide these things from the wise and understanding, and didst reveal them unto babes (Matt 11:25)
And unto them is fulfilled the prophecy of Isaiah, which saith, By hearing ye shall hear, and shall in no wise understand; And seeing ye shall see, and shall in no wise perceive: For this people's heart is waxed gross, And their ears are dull of hearing, And their eyes they have closed; Lest haply they should perceive with their eyes, And hear with their ears, And understand with their heart, And should turn again, And I should heal them. But blessed are your eyes, for they see; and your ears, for they hear (Matt. 13:14-16)
The word mystery in Col.4 is in the context of what Paul was making known in his preaching
to those outside. This is in the context of talking to the unbelievers, those outside the Church. The Church didnt put Paul in prison. But it is interesting that the RCC put people in prison, burned them. And burned bibles and books, and kept the people in the dark, and kept the liturgy in Latin for centuries.
praying at the same time for us as well, that God will open up to us a door for the word, so that we may speak forth the mystery of Christ, for which I have also been imprisoned; 4 that I may make it clear in the way I ought to speak 5 Conduct yourselves with wisdom toward outsiders, making the most of the opportunity. 6 Let your speech always be with grace, as though seasoned with salt, so that you will know how you should respond to each person (Col.4:3-5)
There is a biblical mystery that has 'not' yet been revealed though*, and it is the mystery of lawlessness and iniquity:
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 (2 Thes.2:7) The Saints, do need to be aware of this mystery, and because it was already at work in the first century. Just saying, at least that mystery is biblical.
(*Unless, you are a full Preterist or possibly a Historist, i am neither)