(30) باب مَنْ نَذَرَ نَذْرًا لاَ يُطِيقُهُ
Narrated Abdullah ibn Abbas:
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.
Reference: Sunan Abi Dawud 3322
In-book reference: Book 22, Hadith 81
English translation: Book 21, Hadith 3316