Hadith 4174 - Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi) - Sahih Al-Bukhari - صحيح البخاري - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

64. Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi) - كتاب المغازى

35) Chapter: The Ghazwa of Al-Hudaibiya

The same narration was told by Majzaa from a man called Uhban bin Aus who was one of those who had witnessed (the Pledge of allegiance beneath) the Tree., and who had some trouble in his knee so that while doing prostrations, he used to put a pillow underneath his knee.

Reference: 4174
English reference: Vol. 5, Book 59, Hadith 491
In-book reference: Book 64, Hadith 216
Grade: Sahih
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35) باب غَزْوَةِ الْحُدَيْبِيَةِ

وَقَوْلِ اللَّهِ تَعَالَى: {لَقَدْ رَضِيَ اللَّهُ عَنِ الْمُؤْمِنِينَ إِذْ يُبَايِعُونَكَ تَحْتَ الشَّجَرَةِ}.

وَعَنْ مَجْزَأَةَ، عَنْ رَجُلٍ، مِنْهُمْ مِنْ أَصْحَابِ الشَّجَرَةِ اسْمُهُ أُهْبَانُ بْنُ أَوْسٍ وَكَانَ اشْتَكَى رُكْبَتَهُ، وَكَانَ إِذَا سَجَدَ جَعَلَ تَحْتَ رُكْبَتِهِ وِسَادَةً‏.‏