Paul speaks of the minds of the Israelite people as objects that could be made hard. This expression means that they were unable to understand what they saw. Alternate translation: "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's 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. Alternate translation: "No one removes the veil, because only in Christ does God remove it" (See: [[rc://en/ta/man/translate/figs-activepassive]])