Whether all the moral precepts of the Old Law belong to the law of nature?
Objections
❌ Objection 1 : It would seem that not all the moral precepts belong to the law of nature. For it is written (Ecclus. 17:9): "Moreover He gave them instructions, and the law of life for an inheritance." But instruction is in contradistinction to the law of nature; since the law of nature is not learnt, but instilled by natural instinct. Therefore not all the moral precepts belong to the natural law.
❌ Objection 2 : Further, the Divine law is more perfect than human law. But human law adds certain things concerning good morals, to those that belong to the law of nature: as is evidenced by the fact that the natural law is the same in all men, while these moral institutions are various for various people. Much more reason therefore was there why the Divine law should add to the law of nature, ordinances pertaining to good morals.
❌ Objection 3 : Further, just as natural reason leads to good morals in certain matters, so does faith: hence it is written (Gal. 5:6) that faith "worketh by charity." But faith is not included in the law of nature; since that which is of faith is above nature. Therefore not all the moral precepts of the Divine law belong to the law of nature.