I was able to go to confession yesterday and ask the parish priest about this, his answer was extremely vague, he didn’t seem to distinguish between mortal and venial but said that anger is “sinful” when it causes us to act or think “abnormally,” I sort of took this mean, it becomes mortally sinful when one hits someone or thinks about hitting someone, should I take it that way? Should I read this explanation into St. Thomas Aquinas’ explanation?
If you want to read what Aquinas had to say, check out
these questions in his Summa.
I’ll preface by saying that I don’t know your full situation, so you’ll have to take what I say and interpret it as best you can.
In short, it seems Aquinas says that anger has competing desires. One is the desire for the good of the angered through just vengeance. The other is the desire for evil upon he who draws your ire. Anger desires evil insofar as it is requisite for just vengeance, which is good. Anger is ethical when the desired vengeance and strength of the passion are reasonable when compared to that which brought forth the anger. He also offers up three stages of anger: bile, ill-will, and rancor. The first is an instantaneous reaction, the second is the ensuing grief that causes anger to fester, and the third is restless and hungry for vengeance.
If your anger is over a petty issue or you haven’t given deliberate thought to doing something egregiously evil (disproportionate to what’s been done to you), then I would not consider the anger a mortal sin. However, ask yourself, if you received the retribution you seek, would you be satisfied? Or would you still be at odds with the person?
In my opinion, if it is within your capacity to be charitable (that is, to emanate God’s love for you through the way you conduct yourself by giving love unto others), then that would be far more advisable. If you can bear the suffering and grief that this person has laid upon you without retaliating, do try to.