Unintentionally vowing to fast for 5 days if Allah cures her mother

Q 3: I went to Al-Haram-ul-Makky (the Sacred Mosque in Makkah) on the first day of Muharram, 1412 A.H. to perform the Fajr (Dawn) Prayer before my mother died. While supplicating to Allah in the Haram, I made a vow that I would observe Sawm (Fast) for five days if Allah restored my mother to health, without intending any Shirk (associating others with Allah in His Divinity or worship).Your Eminence, my question is: Was my vow Islamically lawful or Bid‘ah (innovation in religion)?I did observe Sawm for one day before she died. I hope that you will guide me as to what I should do concerning this vow. May Allah safeguard you and guide you on the right path!

A: It is obligatory on you to fulfill your vow if Allah restored your mother to health, because it was a vow of obedience. It was authentically reported that the Prophet (peace be upon him) said, “Anyone who vows to obey Allah, should obey Him and anyone who vows to disobey Allah, should not disobey Him.” May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.