Catechism of the Catholic Church: 66 “The Christian economy, therefore, since it is the new and definitive Covenant, will never pass away; and no new public revelation is to be expected before the glorious manifestation of our Lord Jesus Christ.” Yet even if Revelation is already complete, it has not been made completely explicit; it remains for Christian faith gradually to grasp its full significance over the course of the centuries.
The CCC teaches that there will not be any new “public revelation”, meaning new Divine Revelation (which includes Sacred Tradition and Sacred Scripture). However, the Magisterium can teach seemingly new doctrines, which were always implicit in Sacred Tradition or Sacred Scripture. As time passes, the Church gradually increases Her understanding of Divine Revelation. Examples of this include the Immaculate Conception and the Assumption of Mary, as well as the path of salvation for non-Christians.
There will be “no new public revelation” before Christ Returns in his “glorious manifestation.” That is an interesting phrasing. My view, which is a minority opinion, is that Christ will return twice, once in a “glorious manifestation” at the end of the second part of the tribulation, and again, centuries later, for the general Resurrection. The teaching that there will be no new public revelation explicitly states a limit to that exclusion, the limit being what I would call the time of Christ’s first return. So, it is possible — this is not a dogma or doctrine, but merely a permissible opinion — it is possible that, when Christ returns at the end of the tribulation, He will teach and this teaching will be written down (Scripture) and He will again give the example of His own life and behavior (Tradition), so that both Sacred Tradition and Sacred Scripture will be augmented at that time. Thus, there may be a third Testament added to the Old Testament and the New Testament after the tribulation.
Sacred Tradition is divided into the Traditions of the Old Covenant and of the New Covenant. And Sacred Scripture is also divided into two parts, the Old and the New. So when Christ returns, each will be completed with a third part, which is a reflection of the Most Holy Trinity.
by
Ronald L. Conte Jr.
Roman Catholic theologian and translator of the Catholic Public Domain Version of the Bible.
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the reproach of Christ 
This makes a lot of sense to me.
Where does that leave Mary’s dictation of her life story to the Medjugorie visionary?
Surely this will have to be given a special status as a dogma of the faith?
What turmoil shall engulf the entire world spiritually and physically……I look around and already see much has begun to happen!
I think the dictation of Mary’s story will remain in private revelation. yes, the tribulation is very near. We are on the threshold.
Perhaps the Third Testament would have teachings or with more clear manifestations or revelations on the Holy Spirit. So each Testament would be a reflection of each Person of the Holy Trinity. 1st) the Father, the 2nd) Son, and 3rd) the Holy Spirit. A more comprehensive Testament in the Holy Spirit with confirmation and support on what the Catholic Church (the Body of Christ) has been teaching on the Holy Trinity, Mary, the communion of Saints, etc. The Holy Spirit is Union as it happened at Pentecost where everybody reunited there understood the language; so by this time, there will be no more separation of main religions.