Is it a mortal sin to break a promise to God?

Say you promise God to fast for months at a time but mess up for a few days, is that mortal sin?

Say you are trying to stop being gluttonous and promise God you will just eat a few reasonable meals, but without the intention of breaking your promise you eat a few ‘big’ meals, is that sin?

These types of “promises” seem to be the territory of people who tend towards scrupulosity or who have OCD issues. I really suggest you get under the care of priest. You should not be undertaking severe forms of fasting, mortification, etc, unless under spiritual direction.

Jacob that doesn’t sound like a mortal sin. You didn’t deliberately break your promise, you said, so that wouldn’t be a mortal sin.
We need to be careful what we promise and not impose on ourselves rigid rules when actually we need to deal with something day by day.
It is more helpful to promise God you will do your best to eat with moderation,
but with His grace and help.

Jesus advises caution regarding making vows
" Simply let your ‘Yes’ be ‘Yes,’ and your ‘No ,’ ‘No’; anything beyond this comes from the evil one" (Matthew 5:37).

Promise God you will try, as human beings can do no more than try. In making a vow you are not called on to make by the Church, is to put yourself in danger of either pride or despair, or anything in between (it is that which Jesus is warning about). We need to have the humility of knowing that we can only day by day respond to God’s grace in our intention to do right and good and to avoid sin

Vows are very particular things --even private vows (not the same by the way for readers-- as simply resolutions).

Vows - even private vows can be good. But yes they need to be entered into carefully. Yes making vows that one is not “called on to make by the Church” to make could perhaps be a danger for some. But I do want to note for readers that one need not be called upon to make such in order to make them. But certainly one does well to seek direction and advice (say from a confessor) and not enter into vows without care.

The person posting though should go discuss any possible vows he has made with his Pastor --who has the authority then to dispense them.

Now I have made promises to God before. I concecrated myself to Mary not knowing it entailed daily rosaries and such. Just reading this post made me remember al my broken promiaes. I know I won’t and dont will to make good on promises I made in haste and without careful discernment…i just went to confession yesterday and now I am windering if I am back in mortal sin by refusing what I promised. :frowning: Am I?

Are you talking about a vow? Or just something you said in private? A vow is a serious thing and if broken, well, its a big offense. Private promises, yes it is a sin as well but its not as grave. I don’t know if its mortal, but you still should confess it.

They were private promises…i was so so looking forward to Communion tomorrow! I dont even remember the things I promised. I think one MAY have involved a daily rosary. But I know its more than I am willing now :frowning:

I wouldn’t consider your examples mortal sins

In my opinion, you should go to confession for this. But, instead of confessing the fact that you “broke” your promise, I would confess the fact that you made a “promise” to God that you could not keep. To recieve absolution for breaking your promise would require firm purpose to not break it again (which is unlikely, since is sounds like the promise itself was unreasonable in nature). Confessing that you made a bad promise to God, however, would require that you resolve to not make anymore promises to God in the future without thinking about them carefully beforehand (which sounds a lot more reasonable to me).

"Also invalid is a vow made out of ignorance or error concerning an element which constitutes the substance of the vow or which amounts to a condition sine qua non (c. 126). Ignorance is lack of knowledge; error is mistaken judgment. Ignorance or error invalidates a vow if the person vowing lacked knowledge of, or erred in judgment about, something that is of the substance of the vow. For example, a woman who, believing her husband to have survived a war, vows in gratitude to go to Mass every day, and only later discovers that he in fact was killed in the final hours of battle, is not bound by the vow.

A condition sine qua non is one which is so important that the vow would not have been taken if it had been known that the condition was not verified or could not be fulfilled. For example, a religious brother, who is unaware of or mistakes the juridical effects of a solemn vow of poverty and believes he can keep property, takes solemn vows in a religious institute on the condition, whether explicit or implicit, that he retain ownership of his goods (cf. C. 688, 4-5)."

I just tend to make them on a whim, and them it is like, ahh, I did it again.

The first example was a previous one, though, with good intentions! I read the dominicans do, or did that.

The second, on a whim, again, but again with good intentions. I did not think I commited mortal sin, but I was not sure so the intention was to go to confession before Mass yesterday but I walked to church and the priest was no longer in the confessional when I got there… I did not take communion, because I was unsure, and the next time for confessions are tuesday at the church I go to.

It feels bad not to recieve communion. I do not think I will recieve it today, because I am still unsure, but I hope to on tuesday.


It’s not mortal i think. Take the example of Saint Peter who promised to Jesus to be with me, to protect him until to die. He was absent to the cross but Jesus gave him to be the pastor of his church. So God is Love, He never Punish us about what we promised to him and never made I Think.

God Bless You,

Most broken promises are mortal sins so that’s why one must be careful not to make them too brutal.

The second one was unintentional so not a mortal sin, and the first one if unintentional is also a venial one or if intentional a mortal one.

But a mere resolution, of which constitutes the difference b/t a promise I do not know, is not a mortal sin to break and not really a sin at all at least in some cases.

But making promises is a good habit to get into, if you can keep them. I would recommend bringing this up to your pastor so that you don’t have to fulfill any unfulfilled promises if you have any, and for help to dispense with or analyze any of your other promises; for pastor is the only one capable of doing these things.

Curious question:

What if you made one out of fear? In a moment of Panic?
Once i couldnt find a sibling at night, we looked everywhere, and i sometimes poke fun at her and as anxious and panicky as I am i promised God to not poke fun at her anymore…i thought she was like kidnapped.

She ended up leaving home to walk around the school nearby to clear her mind.

I promised god if he ended the horrible pain in my eyes I’d stop masturbating for a week. Then I convivially broke my promise. Is this a mortal sin??

I sinned and I promised God that I wasn’t going to play video games and hear music that I like until i lost weight, I already broken them and have confessed to a priest, should I tell the priest the whole story or should I keep the promise until i complete it , pls and thank you

God having lot’s of love, they do not punish people if they do wrong but they relize that you do wrong so that next time you don’t repeat same mistake. If you promise with god or you spoul your promise god never punish you for this. Because they love every people in the word.

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