And with the same chain of narration (it is narrated from Sayyiduna Ibn Abbas, may Allah be pleased with them both) that Sayyiduna Sa'd bin Ubadah, may Allah be pleased with him, asked the Messenger of Allah, peace and blessings be upon him, about an issue: My mother has passed away and she had a vow (which was obligatory) that she did not fulfill? So the Messenger of Allah, peace and blessings be upon him, said: "Fulfill (the vow) on her behalf."

It is narrated from the wife of the Prophet, Sayyida Aisha (may Allah be pleased with her), that the Messenger of Allah (peace and blessings be upon him) said: "Whoever makes a vow to obey Allah, let him obey Allah; and whoever makes a vow to disobey Allah, let him not disobey Allah."