infuses it, Who stands in relation to the
infusion and safekeeping of charity, as the sun does to the diffusion
of light in the air, as stated above (A. 10, Obj. 3). Consequently,
just as the light would cease at once in the air, were an obstacle
placed to its being lit up by the sun, even so charity ceases at once
to be in the soul through the placing of an obstacle to the
outpouring of charity by God into the soul.

Now it is evident that through every mortal sin which is contrary to
God's commandments, an obstacle is placed to the outpouring of
charity, since from the very fact that a man chooses to prefer sin to
God's friendship, which requires that we should obey His will, it
follows that the habit of charity is lost at once through one mortal
sin. Hence Augustine says (Gen. ad lit. viii, 12) that "man is
enlightened by God's presence, but he is darkened at once by God's
absence, because distance from Him is effected not by change of place
but by aversion of the will."

Reply Obj. 1: This saying of Origen may be understood, in one way,
that a man who is in the state of perfection, does not suddenly go so
far as to commit a mortal sin, but is disposed thereto by some
previous negligence, for which reason venial sins are said to be
dispositions to mortal sin, as stated above (I-II, Q. 88, A. 3).
Nevertheless he falls, and loses charity through the one mortal sin
if he commits it.

Since, however, he adds: "If some slight slip should occur, and he
recover himself quickly he does not appear to fall altogether," we
may reply in another way, that when he speaks of a man being emptied
and falling away altogether, he means one who falls so as to sin
through malice; and this does not occur in a perfect man all at once.

Reply Obj. 2: Charity may be lost in two ways; first, directly, by
actual contempt, and, in this way, Peter did not lose charity.
Secondly, indirectly, when a sin is committed against charity,
through some passion of desire or fear; it was by sinning against
charity in this way, that Peter lost charity; yet he soon recovered
it.

The Reply to the Third Objection is evident from what has been said.

Reply Obj. 4: Not every inordinate affection for things directed to
the end, i.e., for created goods, constitutes a mortal sin, but only
such as is directly contrary to the Divine will; and then the
inordinate affection is contrary to charity, as stated.

Reply Obj. 5: Charity denotes union with God, whe