Fulfilling a shevua with maaser kesafim
Shalom kevod HaRav,
I took a shevuah to pay a certain amount of money to tzedaka if I would not fulfill certain things. I did not fulfill them, and thus I am obligated to pay the money by my shevuah.
Due to the considerable amount, it is currently difficult for me to pay the money out of extra funds. Can I pay it out of my normal maaser kesafim money?
No, maaser money may not be used. Once a person creates an obligation to tzedaka he may not pay it off with maaser money. Maaser money should be given from money he is not previously obligated to give.
However, if it is a large sum of money which you can’t afford along with maaser, you may at this time be exempt from maaser. Your neder to give tzedaka is obligatory. Maaser kesafim on the other hand is only a minhag [acc. to many opinions], and even if you are accustomed to giving maaser this is only when you can afford it.
If you wish to keep giving maaser, and it is tight, another option is to deduct your household expenses before you determine your maaser. This is a minority opinion, but you may rely on it if otherwise giving maaser fully is not feasible at this time.