Does mortal sin really require grave matter?

Is it a mortal sin to do something that is not gravely immoral if you believe that it is? In other words, are you always committing a mortal sin if you think you are?

Dear M,

One of the requirements for a sin to be mortal is that it be grave matter. If you believe that forgetting to say your morning prayers is a mortal sin, then you have a problem with impaired judgment. You are not able to always distinguish between grave and light matter. We call this scrupulosity.

For a sin to be mortal, the act must be grave in matter—objectively evil. One has to know that it is evil. And one must freely choose it. If any one of these requirements is absent, the act is not mortally sinful.

On the other hand, if you deliberately put poison in someone’s food with the intention of murdering that person, and the person doesn’t die. You are still guilty of the sin of murder. All the requirements for mortal sin are present.

Fr. Vincent Serpa, O.P.

Dear P,

It is difficult for us to avoid projecting our earthly experience on to heaven. We tend to imagine experiencing ourselves in heaven as we experience ourselves here. Heaven is out of this world—in more ways than we can imagine!

The direct experience of infinite good, which is who God is, is so all-encompassing that nothing less will be able to have an effect on it. Also–it is important to remember that anyone who is in hell, has freely chosen to be there by his or her choice against God.

Fr. Vincent Serpa, O.P.

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