CCC 2067 The Ten Commandments state what is required in the love of God and love of neighbor. The first three concern love of God, and the other seven love of neighbor.
As charity comprises the two commandments to which the Lord related the whole Law and the prophets. .. so the Ten Commandments were themselves given on two tablets. Three were written on one tablet and seven on the other.1
1 St. Augustine, Sermo 33, 2, 2: PL 38, 208.