I asked ʿAʿishah about wiping over the khuffain [leather slippers]. She said: Go to ‘Ali, for he knows more about that than me. So I went to ʿAli ؓ and asked him about wiping over the khuffain. He said: The Messenger of Allah ﷺ used to tell us to wipe over the khuffain for one day and night, and for the traveller it is three [days and nights]. Yazeed told us: Hajjaj narrated to us and attributed it to the Prophet ﷺ.
ائْتِ عَلِيًّا فَهُوَ أَعْلَمُ بِذَلِكَ مِنِّي قَالَ فَأَتَيْتُ عَلِيًّا فَسَأَلْتُهُ عَنِ الْمَسْحِ عَلَى الْخُفَّيْنِ قَالَ فَقَالَ كَانَ رَسُولُ اللهِ ﷺ يَأْمُرُنَا أَنْ نَمْسَحَ عَلَى الْخُفَّيْنِ يَوْمًا وَلَيْلَةً وَلِلْمُسَافِرِ ثَلاثًا