Whether all the moral precepts of the Old Law are reducible to the ten precepts of the decalogue?

❌ Objection 1 : It would seem that not all the moral precepts of the Old Law are reducible to the ten precepts of the decalogue. For the first and principal precepts of the Law are, "Thou shalt love the Lord thy God," and "Thou shalt love thy neighbor," as stated in Mt. 22:37,39. But these two are not contained in the precepts of the decalogue. Therefore not all the moral precepts are contained in the precepts of the decalogue.

❌ Objection 2 : Further, the moral precepts are not reducible to the ceremonial precepts, but rather vice versa. But among the precepts of the decalogue, one is ceremonial, viz. "Remember that thou keep holy the Sabbath-day." Therefore the moral precepts are not reducible to all the precepts of the decalogue.

❌ Objection 3 : Further, the moral precepts are about all the acts of virtue. But among the precepts of the decalogue are only such as regard acts of justice; as may be seen by going through them all. Therefore the precepts of the decalogue do not include all the moral precepts.