"But their minds were hardened." Paul speaks of the minds of the Israelite people as objects that could be closed or made hard. This expression means that they were unable to understand what they saw. AT: "But the Israelites could not understand what they saw" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Just as the Israelites could not see the glory on Moses' face because he covered his face with a veil, there is a spiritual veil that prevents people from understanding when they read the old covenant. (See: [[rc://en/ta/man/translate/figs-metaphor]])
Here both occurrences of the word "it" refer to "the same veil." This can be stated in active form. AT: "No one removes the veil, because only in Christ does God remove it" (See: [[rc://en/ta/man/translate/figs-activepassive]])