Reply Obj. 2:  All the differences assigned between the Old and New Laws are gathered from their relative perfection and imperfection.  For the precepts of every law prescribe acts of virtue.  Now the imperfect, who as yet are not possessed of a virtuous habit, are directed in one way to perform virtuous acts, while those who are perfected by the possession of virtuous habits are directed in another way.  For those who as yet are not endowed with virtuous habits, are directed to the performance of virtuous acts by reason of some outward cause:  for instance, by the threat of punishment, or the promise of some extrinsic rewards, such as honor, riches, or the like.  Hence the Old Law, which was given to men who were imperfect, that is, who had not yet received spiritual grace, was called the “law of fear,” inasmuch as it induced men to observe its commandments by threatening them with penalties; and is spoken of as containing temporal promises.  On the other hand, those who are possessed of virtue, are inclined to do virtuous deeds through love of virtue, not on account of some extrinsic punishment or reward.  Hence the New Law which derives its pre-eminence from the spiritual grace instilled into our hearts, is called the “Law of love”:  and it is described as containing spiritual and eternal promises, which are objects of the virtues, chiefly of charity.  Accordingly such persons are inclined of themselves to those objects, not as to something foreign but as to something of their own.  For this reason, too, the Old Law is described as “restraining the hand, not the will” [Peter Lombard, Sent. iii, D, 40]; since when a man refrains from some sins through fear of being punished, his will does not shrink simply from sin, as does the will of a man who refrains from sin through love of righteousness:  and hence the New Law, which is the Law of love, is said to restrain the will.

Nevertheless there were some in the state of the Old Testament who, having charity and the grace of the Holy Ghost, looked chiefly to spiritual and eternal promises:  and in this respect they belonged to the New Law.  In like manner in the New Testament there are some carnal men who have not yet attained to the perfection of the New Law; and these it was necessary, even under the New Testament, to lead to virtuous action by the fear of punishment and by temporal promises.

But although the Old Law contained precepts of charity, nevertheless it did not confer the Holy Ghost by Whom “charity . . . is spread abroad in our hearts” (Rom. 5:5).

Reply Obj. 3:  As stated above (Q. 106, AA. 1, 2), the New Law is called the law of faith, in so far as its pre-eminence is derived from that very grace which is given inwardly to believers, and for this reason is called the grace of faith.  Nevertheless it consists secondarily in certain deeds, moral and sacramental:  but the New Law does not consist chiefly in these latter things, as did the Old Law.  As to those under the Old Testament who through faith were acceptable to God, in this respect they belonged to the New Testament:  for they were not justified except through faith in Christ, Who is the Author of the New Testament.  Hence of Moses the Apostle says (Heb. 11:26) that he esteemed “the reproach of Christ greater riches than the treasure of the Egyptians.” ________________________