I’ve made what I consider a private vow. Anyway, I promised to God not to fall in a certain sin, and if I fell, I would abandon two things in my life (which are good, btw), as a penance. I made this kinda out of anger with myself for committing this sin. Then, I researched how vows work and all that… and I want to commute my vow for two reasons:
a) If I end up committing that sin again, I won’t lose two things that I consider important to myself
b) I could instead do some good to someone, instead of just a personal sacrifice.
I understand that I can only commute my vow to something of equal or greater good, so I think that switching it for something less important, but that’ll help someone fits that.
Is my way of thinking right? I remained vague on purpose about some things, but I think the situation is clear enough to be understood.
Taking private vows is a delicate matter that should only be done under the care of a spiritual director. It would also be a good idea not to seek further advice on private vows from an internet forum, where varying opinions abound, particularly if one suffers from scruples.
Father is quite correct in the advice he has already given you. There are very few on this forum who are ordained or are competent to answer questions of this nature.
As a priest, rather than commutation, I would frankly suggest that you seek a conditional dispensation from this private vow – if it actually was such; that could not be determined without seeing the formula. The dispensation would be done according to the norms of canon 1196; the easiest method being recourse to your pastor.
Given what you say, the vow, even if properly formulated, would very likely be null under the provisions of canon 1191 §3.
Your method of proceeding is not sound with regard to the spiritual life and the overcoming of sin, since that is not the purpose of private vows.
Father is most correct when he says that any private vows should be very carefully, cautiously, and thoughtfully made, with sufficient knowledge and understanding of the theology of vows, according to the mind and thought of the Church on this matter, and with the assistance and guidance of a spiritual director.