the commandments: "You shall not commit adultery, You shall not kill, You shall not steal, You shall not covet," and any other commandment, are summed up in this sentence: "You shall love your neighbor as yourself." Love does no wrong to a neighbor; therefore love is the fulfilling of the law. 10
Catechism number 2056
The word "Decalogue" means literally "ten words."11 God revealed these "ten words" to his people