written (Lev. 18:5): "Keep My laws and My
judgments, which if a man do, he shall live in them." But the
spiritual life of man is through justice. Therefore the fulfilling of
the precepts of the Law was a cause of justification.

Obj. 3: Further, the Divine law is more efficacious than human law.
But human law justifies man; since there is a kind of justice
consisting in fulfilling the precepts of law. Therefore the precepts
of the Law justified man.

_On the contrary,_ The Apostle says (2 Cor. 3:6): "The letter
killeth": which, according to Augustine (De Spir. et Lit. xiv),
refers even to the moral precepts. Therefore the moral precepts did
not cause justice.

_I answer that,_ Just as "healthy" is said properly and first of that
which is possessed of health, and secondarily of that which is a sign
or a safeguard of health; so justification means first and properly
the causing of justice; while secondarily and improperly, as it were,
it may denote a sign of justice or a disposition thereto. If justice
be taken in the last two ways, it is evident that it was conferred by
the precepts of the Law; in so far, to wit, as they disposed men to
the justifying grace of Christ, which they also signified, because as
Augustine says (Contra Faust. xxii, 24), "even the life of that
people foretold and foreshadowed Christ."

But if we speak of justification properly so called, then we must
notice that it can be considered as in the habit or as in the act: so
that accordingly justification may be taken in two ways. First,
according as man is made just, by becoming possessed of the habit of
justice: secondly, according as he does works of justice, so that in
this sense justification is nothing else than the execution of
justice. Now justice, like the other virtues, may denote either the
acquired or the infused virtue, as is clear from what has been stated
(Q. 63, A. 4). The acquired virtue is caused by works; but the
infused virtue is caused by God Himself through His grace. The latter
is true justice, of which we are speaking now, and in this respect of
which a man is said to be just before God, according to Rom. 4:2: "If
Abraham were justified by works, he hath whereof to glory, but not
before God." Hence this justice could not be caused by moral
precepts, which are about human actions: wherefore the moral precepts
could not justify man by causing justice.

If, on the other hand, by justification we understand the execution
of