If a person makes a vow to God (not knowing it was wrong), that if you give me this, I’ll give this much money & read 500 Yaseen, but they don’t get the thing, are they obligated to fulfill the vow? What happens if they cant (financially)?
A vow is an act of worship which a morally responsible Muslim makes obligatory upon himself. For example, saying “if X happens, I will do Y” would be considered a vow.
The expiation for breaking an oath is to set free a slave, or to feed or clothe ten poor persons. Whoever cannot do any of those things should fast for three days.