If someone makes a small promise to God (such as “I promise I won’t use the internet and will read a book for an hour”), and then breaks it, is this mortal?
I want to say no, that it is not a grave matter to break a small promise, assuming of course that it wasn’t a promise to not commit a mortal sin. It is certainly venial at least, on account of Jesus saying to let your “yes mean yes and no mean no”.
I ask as I did break such a small promise today, after only going to confession this morning, and I want to know if I can receive communion at mass tonight. I imagine there will be differing opinions. I am in the “not a mortal sin” camp, but I would be interested in hearing what you all think.