Sunan Abi Dawud
Oaths and Vows (Kitab Al-Aiman Wa Al-Nudhur)
كتاب الأيمان والنذور
Chapter 1242: The One Who Vows To Give His Wealth In Charity
فِيمَنْ نَذَرَ أَنْ يَتَصَدَّقَ بِمَالِهِ
I said: Messenger of Allah, to make my atonement complete I should divest myself of my all property as sadaqah (alms) for Allah and His apostle. He said: No. I said: The half of it. He said: No. I said: Then a third of it. He said: Yes. I said: I shall retain the portion I have at Khaybar.
Chapter 1243: On A Man Who Takes Vows For A Thing Over Which He has no control
مَنْ نَذَرَ نَذْرًا لاَ يُطِيقُهُ
The Prophet (ﷺ) said: If anyone takes a vow but does not name it, its atonement is the same as that for an oath, if anyone takes a vow to do an act of disobedience, its atonement is the same as that for an oath, if anyone takes a vow he is unable to fulfill, its atonement is the same as that for an oath, but if anyone takes a vow he is able to fulfill, he must do so.
Abu Dawud said: This tradition has been transmitted by Waki' and others on the authority of 'Abd Allah b. Sa'id b. Abi al-Hind, but they traced it no farther back than Ibn 'Abbas.
Chapter 1244: On A Man Who Takes A Vow But Does Not Name it
مَنْ نَذَرَ نَذْرًا لَمْ يُسَمِّهِ
The Messenger of Allah (ﷺ) as saying: The atonement for a vow is the same as for an oath.
Abu Dawud said: This tradition has also been transmitted by 'Amr b. al-Harith from Ka'b b. 'Alqamah, from Ibn Shamasah on the authority of 'Uqbah.
A similar tradition has also been transmitted by 'Uqbah b. 'Amir from the Prophet (ﷺ) through a different chain of narrators.
Chapter 1245: If A Person Made A Vow In Jahiliyyah Then Entered Islam
مَنْ نَذَرَ فِي الْجَاهِلِيَّةِ ثُمَّ أَدْرَكَ الإِسْلاَمَ
That 'Umar said: Messenger of Allah, I took a vow in pre-Islamic times that I would stay in the sacred mosque (Masjid Haram) as a devotion (i'tikaf). The Prophet (ﷺ) said: Fulfill your vow.