Question:
'A' had an item he planned to give away to a tzedaka (equipment for disabled person). He verbalised this by telling 'B' that he was going to do this. C (a real estate agent) came to A's house to view the house and saw the item and offered to buy it. A agreed and sold it to C. Now A thinks he should not have done this because he had decided to give it to a tzedaka and had verbalised this thought. What should A do now? C has already paid for the item and taken it.
Answer:
Hello,
A’s should not have sold the item to the real estate agent, however post-facto, if you said hatoras nedarim and were “ mores moda’ah” or if you said along with the chazzan during kol Nidrei, we can rely that the neder to give tzedakah which is like a neder to do a mitzva, is nullified by you being moser moda’ah.
Best wishes
Sources:
שו"ת מנחת שלמה ח"א סימן צא אות כ', וכ"כ בס' כל נדרי פס"א אות ג'.