The first reading refers to an incident in Chapter Thirty-four of the Book of Exodus. One time when Moses came down from Mont Sinai, the people ran away from him. They were frightened because his face had taken on a radiance from his conferring face-to-face with God.
Paul recalled that incident because it exemplified what happens to our souls when we spend time in intimate prayer with God. In tomorrow’s first reading Paul tells us, “All of us, gazing with unveiled face on the glory of the Lord, are being transformed into the same image from glory to glory.”
In saying we are transformed “from glory to glory” Paul was saying that there is progress in holiness We become like God by gazing at him, and we become more like him with every one of our confrontations with him.