Grave matter to do something if we're unsure whether it's grave matter?

I recently read a post stating that if we don’t have full knowledge on whether an action is grave matter, and commit it anyway, it would become grave matter regardless. Is this true, and to what extent? How much are we allowed to trust in our judgment - for example, if I’m confident that I can tell a joke sinlessly (with reason to believe it won’t lower the opinions of someone, etc)?

Your confident it is not a sin - so where is your grave matter? Where is your uncertainty that it is a sin or not?

Do you have reason to believe your mistaken?

I assume your conscience is formed according to the teachings of the Church…and your judging that Z joke is not sinful…

We are to form our consciences and make judgments.

Ones confessor to can assist etc.

Compendium issued by Pope Benedict XVI
395. When does one commit a mortal sin?**


One commits a mortal sin when there are simultaneously present: grave matter, full knowledge, and deliberate consent. This sin destroys charity in us, deprives us of sanctifying grace, and, if unrepented, leads us to the eternal death of hell. It can be forgiven in the ordinary way by means of the sacraments of Baptism and of Penance or Reconciliation.

396. When does one commit a venial sin?


One commits a venial sin, which is essentially different from a mortal sin, when the matter involved is less serious or, even if it is grave, when full knowledge or complete consent are absent. Venial sin does not break the covenant with God but it weakens charity and manifests a disordered affection for created goods. It impedes the progress of a soul in the exercise of the virtues and in the practice of moral good. It merits temporal punishment which purifies.

If one is reasonably unsure if Z is gravely sinful… one should resolve this before acting. Such as by asking ones confessor…checking the Catechism or some other reliable source etc.

Now that being said - those who are scrupulous can be in a rather different boat -they can mistake their scruples and fears for reasonable concerns of conscience - they should have a regular confessor who can direct them and who can give them principles even to apply in overcoming their scruples.

I suppose I may have been underestimating how much we are allowed to trust in our judgment. Obviously, we have no way of undoubtedly knowing whether every last one of our actions constitute grave matter, so I suppose we are allowed to have rational confidence in our judgment. I need to make sure I don’t worry excessively about being wrong and maintain that confidence.

We are called to holiness and we express our belief in “all that is seen and unseen.”

I am in no position to judge or condemn (none of us are) but we should all consider not just the substance of the joke we want to tell, and the consequences of telling it.

I don’t like priests telling jokes at Mass, as if to liven the party. And, this one retired, visiting priest told an adam and eve “joke” that was double edged, was insulting to both men and women. I considered throwing my hymnal a him, but we don’t have hymnals or anything substantial enough to knock some sense into him.

We are called to be different from “the world.”

As a Catholic, you should read the Catechism. If you haven’t done so, make it a new year’s resolution. read 10 pages per day. It’s not that hard or that difficult to understand. Use a pencil and paper and write down paragraph numbers you want to go back to, to study more. (to your specific question, read para. 1735)

Just the other day, the Pope was saying that priests should not throw laws and commandments at people, like stones. And that is because the laws oversimplify everything. having noted that, we should (me too) be conservative and restrain ourselves because of human dignity and sanctity. I’ve got a big mouth and this is not easy medicine for me, either.

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