(42) باب مَا الْوَاجِبُ عَلَى مَنْ أَوْجَبَ عَلَى نَفْسِهِ نَذْرًا فَعَجَزَ عَنْهُ .
It was narrated that Anas said:
"The Messenger of Allah passed by an old man who was being supported between two men and said: 'What is the matter with him?' They said: 'He vowed to walk.' He said: 'Allah has no need for him to torture himself. Tell him to ride.'" So he was told to ride.
Reference: Sunan an-Nasa'i 3853
In-book reference: Book 35, Hadith 93
English translation: Vol. 4, Book 35, Hadith 3884