CCC 2118
Life in Christ›SECTION TWO THE TEN COMMANDMENTS›CHAPTER ONE YOU SHALL LOVE THE LORD YOUR GOD WITH ALL YOUR HEART, AND WITH ALL YOUR SOUL, AND WITH ALL YOUR MIND›III. "You Shall Have No Other Gods Before Me"
God's first commandment condemns the main sins of irreligion: tempting God, in words or deeds, sacrilege, and simony.