of these amounts to a sin through certain malice; for then alone does anyone sin through certain malice, when his will is moved to evil of its own accord.  This may happen in two ways.  First, through his having a corrupt disposition inclining him to evil, so that, in respect of that disposition, some evil is, as it were, suitable and similar to him; and to this thing, by reason of its suitableness, the will tends, as to something good, because everything tends, of its own accord, to that which is suitable to it.  Moreover this corrupt disposition is either a habit acquired by custom, or a sickly condition on the part of the body, as in the case of a man who is naturally inclined to certain sins, by reason of some natural corruption in himself.  Secondly, the will, of its own accord, may tend to an evil, through the removal of some obstacle:  for instance, if a man be prevented from sinning, not through sin being in itself displeasing to him, but through hope of eternal life, or fear of hell, if hope give place to despair, or fear to presumption, he will end in sinning through certain malice, being freed from the bridle, as it were.

It is evident, therefore, that sin committed through certain malice, always presupposes some inordinateness in man, which, however, is not always a habit:  so that it does not follow of necessity, if a man sins through certain malice, that he sins through habit.

Reply Obj. 1:  To do an action as an unjust man does, may be not only to do unjust things through certain malice, but also to do them with pleasure, and without any notable resistance on the part of reason, and this occurs only in one who has a habit.

Reply Obj. 2:  It is true that a man does not fall suddenly into sin from certain malice, and that something is presupposed; but this something is not always a habit, as stated above.

Reply Obj. 3:  That which inclines the will to evil, is not always a habit or a passion, but at times is something else.  Moreover, there is no comparison between choosing good and choosing evil:  because evil is never without some good of nature, whereas good can be perfect without the evil of fault. ________________________

FOURTH ARTICLE [I-II, Q. 78, Art. 4]

Whether It Is More Grievous to Sin Through Certain Malice Than
Through Passion?

Objection 1:  It would seem that it is not more grievous to sin through certain malice than through passion.  Because ignorance excuses from sin either altogether or in part.  Now ignorance is greater in one who sins through certain malice, than in one who sins through passion; since he that sins through certain malice suffers from the worst form of ignorance, which according to the Philosopher (Ethic. vii, 8) is ignorance of principle, for he has a false estimation of the end, which is the principle in matters of action.  Therefore there is more excuse for one who sins through certain malice, than for one who sins through passion.