Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bayhaqi:348al-Faqīh Abū Bakr Muḥammad b. Bakr al-Ṭūsī > Abū Bishr Muḥammad b. Aḥmad b. Ḥāḍir > Abū al-ʿAbbās al-Sirāj > Muḥammad b. Ismāʿīl b. Abū Samīnah > al-Qāsim b. Muḥammad b. Yazīd al-Jarmī > Sufyān al-Thawrī And Hishām b. Saʿd > Zayd b. Aslam > ʿAṭāʾ b. Yasār

[Machine] Ibn Abbas said to me, "Shall I not show you the Prophet's ﷺ ablution?" So, he performed ablution once, then washed his feet while his sandals were still on. This indicates that he washed his feet with the sandals on. Allah knows best.  

البيهقي:٣٤٨أَخْبَرَنَا الْفَقِيهُ أَبُو بَكْرٍ مُحَمَّدُ بْنُ بَكْرٍ الطُّوسِيُّ أنا أَبُو بِشْرٍ مُحَمَّدُ بْنُ أَحْمَدَ بْنِ حَاضِرٍ ثنا أَبُو الْعَبَّاسِ السِّرَاجُ ثنا مُحَمَّدُ بْنُ إِسْمَاعِيلَ بْنِ أَبِي سَمِينَةَ ثنا الْقَاسِمُ بْنُ مُحَمَّدِ بْنِ يَزِيدَ الْجَرْمِيُّ ثنا سُفْيَانُ الثَّوْرِيُّ وَهِشَامُ بْنُ سَعْدٍ كِلَاهُمَا عَنْ زَيْدِ بْنِ أَسْلَمَ عَنْ عَطَاءِ بْنِ يَسَارٍ قَالَ

قَالَ لِي ابْنُ عَبَّاسٍ أَلَا أُرِيكَ وُضُوءَ رَسُولِ اللهِ ﷺ؟ فَتَوَضَّأَ مَرَّةً ثُمَّ غَسَلَ رِجْلَيْهِ وَعَلَيْهِ نَعْلُهُ فَهَذَا يَدُلُّ عَلَى أَنَّهُ غَسَلَ رِجْلَيْهِ فِي النَّعْلَيْنِ وَاللهُ أَعْلَمُ