Sahih Bukhari Volume 8, Book 81, Hadith 6450

حَدَّثَنَا الْحُمَيْدِيُّ، حَدَّثَنَا سُفْيَانُ، حَدَّثَنَا الأَعْمَشُ، قَالَ سَمِعْتُ أَبَا وَائِلٍ، قَالَ عُدْنَا خَبَّابًا فَقَالَ هَاجَرْنَا مَعَ النَّبِيِّ صلى الله عليه وسلم نُرِيدُ وَجْهَ اللَّهِ، فَوَقَعَ أَجْرُنَا عَلَى اللَّهِ، فَمِنَّا مَنْ مَضَى لَمْ يَأْخُذْ مِنْ أَجْرِهِ، مِنْهُمْ مُصْعَبُ بْنُ عُمَيْرٍ قُتِلَ يَوْمَ أُحُدٍ، وَتَرَكَ نَمِرَةً فَإِذَا غَطَّيْنَا رَأْسَهُ بَدَتْ رِجْلاَهُ، وَإِذَا غَطَّيْنَا رِجْلَيْهِ بَدَا رَأْسُهُ، فَأَمَرَنَا النَّبِيُّ صلى الله عليه وسلم أَنْ نُغَطِّيَ رَأْسَهُ، وَنَجْعَلَ عَلَى رِجْلَيْهِ مِنَ الإِذْخِرِ، وَمِنَّا مَنْ أَيْنَعَتْ لَهُ ثَمَرَتُهُ فَهْوَ يَهْدُبُهَا‏.‏

Narrated By Abu Wail : We paid a visit to Khabbab who was sick, and he said, "We migrated with the Prophet for Allah's Sake and our wages became due on Allah. Some of us died without having received anything of the wages, and one of them was Mus'ab bin 'Umar, who was martyred on the day of the battle of Uhud, leaving only one sheet (to shroud him in). If we covered his head with it, his feet became uncovered, and if we covered his feet with it, his head became uncovered. So the Prophet ordered us to cover his head with it and put some Idhkhir (a kind of grass) over his feet. On the other hand, some of us have had the fruits (of our good deed) and are plucking them (in this world)."