Dr. Matthew Barrett in the opening paragraph of his article, What is So New About the New Covenant? Exploring the Contours of Paul’s New Covenant Theology in 2 Corinthians 3, written for The Southern Baptist Journal of Theology:
Second Corinthians 3 is a hotly debated and difficult text. For example, Thomas Schreiner says 2 Corinthians 3 is “one of the most controverted texts in the Pauline corpus,” and is “full of exegetical difficulties and knotty problems.” David Garland believes the passage is “notoriously obscure” and Anthony Hanson says it is the “mount Everest of Pauline texts as far as difficulty is concerned—or should we rather call it the sphinx among texts, since its difficulty lies in its enigmatic quality rather than its com- plexity?” The result has been a hermeneutical maze of literature almost impossible to navigate.
We're currently working through 2 Corinthians as a church and I've been attempting to climb "Mount Everest" all week long in preparation for my sermon on 2 Corinthians 3:7–18. I feel like I need at least another month or two to write this one.