y doing something not only against the
favor itself, but also against the form of the favor received. If
this form be considered on the part of the benefactor, it is the
remission of something due to him; wherefore he who does not forgive
his brother when he asks pardon, and persists in his hatred, acts
against this form. If, however, this form be taken in regard to the
penitent who receives this favor, we find on his part a twofold
movement of the free-will. The first is the movement of the free-will
towards God, and is an act of faith quickened by charity; and against
this a man acts by apostatizing from the faith. The second is a
movement of the free-will against sin, and is the act of penance.
This act consists first, as we have stated above (Q. 85, AA. 2, 5) in
man's detestation of his past sins; and against this a man acts when
he regrets having done penance. Secondly, the act of penance consists
in the penitent purposing to subject himself to the keys of the
Church by confession, according to Ps. 31:5: "I said: I will confess
against myself my injustice to the Lord: and Thou hast forgiven the
wickedness of my sin": and against this a man acts when he scorns to
confess as he had purposed to do.

Accordingly it is said that the ingratitude of sinners is a special
cause of the return of sins previously forgiven.

Reply Obj. 1: This is not said of these sins as though they were more
grievous than others, but because they are more directly opposed to
the favor of the forgiveness of sin.

Reply Obj. 2: Even venial sins and original sin return in the way
explained above, just as mortal sins do, in so far as the favor
conferred by God in forgiving those sins is despised. A man does not,
however, incur ingratitude by committing a venial sin, because by
sinning venially man does not act against God, but apart from Him,
wherefore venial sins nowise cause the return of sins already
forgiven.

Reply Obj. 3: A favor can be weighed in two ways. First by the
quantity of the favor itself, and in this way innocence is a greater
favor from God than penance, which is called the second plank after
shipwreck (cf. Q. 84, A. 6). Secondly, a favor may be weighed with
regard to the recipient, who is less worthy, wherefore a greater
favor is bestowed on him, so that he is the more ungrateful if he
scorns it. In this way the favor of the pardon of sins is greater
when bestowed on one who is altogether unworthy, so that the
ingratitude