CCC 2059 The “ten words” are pronounced by God in the midst of a theophany (“The LORD spoke with you face to face at the mountain, out of the midst of the fire.”1). They belong to God’s revelation of himself and his glory. The gift of the Commandments is the gift of God himself and his holy will. In making his will known, God reveals himself to his people.
1 Deut 5:4.