The Ruling on Fulfilling a Vow Conditioned on Ability

Question:
My mother made a vow that if my brother, who was young at the time, were able to draw water for her from a certain well, she would perform a specific act of worship for her neighbors. However, the well collapsed and dried up before my brother grew up and was able to bring water from it. Does the vow become due?

Answer:
Yes, if she is able to do so. If the well were sound and she could bring water from it, she would fulfill her vow. The Prophet (peace and blessings be upon him) said: . Because her intention, when she grows up and becomes able to do these things, is that if she grows up and is able to bring water, provided the well is sound, she will fulfill her vow. The Prophet (peace and blessings be upon him) said: . And honoring the guests is obedience to Allah. Allah praised the one who fulfills his vow, and He said, Exalted is He: Yes. May Allah reward you with good.