Is this a mortal sin? Please help me


Hi. This is my first post on this forum. I am just looking for opinions on whether or not it is a mortal sin to refer to a fly in your house as “that d*** fly.” Thanks!


Hello and welcome.

The Catechism of the Catholic Church says:

1857 For a sin to be mortal, three conditions must together be met: “Mortal sin is sin whose object is grave matter and which is also committed with full knowledge and deliberate consent.”

If the statement has no meaning to the declarant beyond some form of “That fly is really annoying” then I would say no, since it does not involve a grave matter that the declarant knows is sinful.

On the other hand, if by making the statement the declarant intends to invoke the power of God to literally cast the fly into the flames of the netherworld, that’s a very serious matter:

2117 All practices of magic or sorcery, by which one attempts to tame occult powers, so as to place them at one’s service and have a supernatural power over others - even if this were for the sake of restoring their health - are gravely contrary to the virtue of religion. These practices are even more to be condemned … when they have recourse to the intervention of demons. … Recourse to so-called traditional cures does not justify either the invocation of evil powers or the exploitation of another’s credulity.

So if the intent is to invoke magical powers from some source to kill the fly and the declarant knows it is contrary to Church teaching and does it anyway, then yes it is a mortal sin, whether the invocation actually kills the fly nor not.


Thank you for the reply! I certainly don’t mean to invoke magic or use divination. I just said it without thinking.


No, it doesn’t seem to be a mortal sin since you were simply cursing due to anger.


The only reason I ask is because I know that the fly is part of God’s creation and I wasn’t sure if using a curse word with something from God’s creation was some sort of blasphemy.


It’s not blasphemy since you weren’t speaking ill of God Himself or sacred people/objects. :slight_smile:




Yes!! A sin crying out to heaven for vengeance!!! Repent!!

Just joking. Try to avoid such language, but I doubt the action you described is a sin.


OK, got another question. I was watching a video on my iPhone from Church Militant TV’s channel. I accidentally closed the window, and said d***. Would that be a mortal sin?


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