9, Art. 9]

Whether One Who Has Already Obtained Grace, Can, of Himself and
Without Further Help of Grace, Do Good and Avoid Sin?

Objection 1: It would seem that whoever has already obtained grace,
can by himself and without further help of grace, do good and avoid
sin. For a thing is useless or imperfect, if it does not fulfil what
it was given for. Now grace is given to us that we may do good and
keep from sin. Hence if with grace man cannot do this, it seems that
grace is either useless or imperfect.

Obj. 2: Further, by grace the Holy Spirit dwells in us, according to
1 Cor. 3:16: "Know you not that you are the temple of God, and that
the Spirit of God dwelleth in you?" Now since the Spirit of God is
omnipotent, He is sufficient to ensure our doing good and to keep us
from sin. Hence a man who has obtained grace can do the above two
things without any further assistance of grace.

Obj. 3: Further, if a man who has obtained grace needs further aid of
grace in order to live righteously and to keep free from sin, with
equal reason, will he need yet another grace, even though he has
obtained this first help of grace. Therefore we must go on to
infinity; which is impossible. Hence whoever is in grace needs no
further help of grace in order to do righteously and to keep free
from sin.

_On the contrary,_ Augustine says (De Natura et Gratia xxvi) that "as
the eye of the body though most healthy cannot see unless it is
helped by the brightness of light, so, neither can a man, even if he
is most righteous, live righteously unless he be helped by the
eternal light of justice." But justification is by grace, according
to Rom. 3:24: "Being justified freely by His grace." Hence even a man
who already possesses grace needs a further assistance of grace in
order to live righteously.

_I answer that,_ As stated above (A. 5), in order to live righteously
a man needs a twofold help of God--first, a habitual gift whereby
corrupted human nature is healed, and after being healed is lifted up
so as to work deeds meritorious of everlasting life, which exceed the
capability of nature. Secondly, man needs the help of grace in order
to be moved by God to act.

Now with regard to the first kind of help, man does not need a
further help of grace, e.g. a further infused habit. Yet he needs the
help of grace in another way, i.e. in order to be moved by God to act
righteously, and this for two reasons: first, for the general reason
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