I know exactly what you mean by “fly out.” I can have a particularly colorful tongue at times even though I do my utmost to be respectful and I wouldn’t consider foul words to be much of a part of my natural vocabulary. I’m a former soldier and cussing was something that everybody just did in that environment, so much so that it gets ingrained in you, so I probably won’t ever completely rid myself of that habit. I also am very turned off when I’m with others that are casually crude in their everyday speech, so I understand that it’s not something I should do. When I’m making a confession I always include it but I’ve never gone to confession just for that.
Do you need to go to confession? If we’re talking profanity (usually describing body parts or functions) rather than blasphemy or irreverence, it depends on the context whether it’s objectively mortal sin. See Michelle Arnold’s response:
forums.catholic-questions.org/showthread.php?t=14494 Obviously the weight of it being a bad habit might mitigate culpability, I would be most concerned that you mentioned doing it in arguments with your wife, and if you’re being deliberately crude, or hurting her feelings, or calling her certain names, that could cross into the territory of grave matter. Otherwise, it might just be rude, and you can be rude without intending to offend. You can’t sin on accident.
In any event, praying for you, and I agree with Mary’s suggestion. Find a substitute word and try to consciously use that in place of actual profanity. Maybe a nonsense word or something harmless (Just say “Bubbles” in as angry voice as you can!) Robbin Williams gave us “Shazzbot,” I worked once with someone who used that fake expletive if he dropped something, it was certainly easier on our customers’ ears if there were any around. That might help train you out of the habit a bit.
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