Of God and His Creatures

The term right may be taken in two senses: (1) as the contradictory of wrong, thus it means not wrong, but permissible. So it is right to wear a red waistcoat. Positive laws can command nothing which is not right to begin with, in this sense. (2) Right may mean requisite, incumbent upon human nature as such, and requiring to be made obligatory upon all, e.g., sobriety and the payment of debts. This sense of right includes the former sense and adds to it. The law commanding such right is not called positive but natural law. St Thomas calls it divine law, meaning the natural law as revealed. Right in this chapter is right in the second sense of the term.

Of God and His Creatures: 3.129