Mishkat al-Masabih 4253
Abu 'Asib said:
God's messenger went out during the night and when he passed me by and called to me I went out to him. He then passed by Abu Bakr, and when he called him he went out to him. He then passed by 'Umar and when he called him he went out to him. He then set off and when he had entered a garden belonging to one of the Ansar he asked the owner of the garden to give us some ripening dates to eat. He brought a bunch and laid it down, and when he and his companions had eaten he called for some cold water, after drinking which he said, "You will be questioned about this bounty on the day of resurrection." Thereupon 'Umar seized the bunch, and when he had thrown it on the ground so that the ripening dates were scattered towards God’s messenger he said, "Messenger of God, shall we be questioned about this on the day of resurrection?" He replied, "Yes, but not for three things: a rag with which a man covers his private parts, or a crumb with which he allays his hunger, or a shelter 1 into which he warms himself to escape heat and cold." 
1. The word is hujr which is basically something forbidden It is then used as a place of protection covered with mud or stone. The following words indicate that something very small is intended. Cf. Mirqat , iv, 397. Pt. 12

Ahmad and Baihaqi, in Shu'ab al-iman , transmitted it.
عَنْ أَبِي عَسِيبٍ قَالَ: خَرَجَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ لَيْلًا فَمَرَّ بِي فَدَعَانِي فَخَرَجْتُ إِلَيْهِ ثُمَّ مَرَّ بِأَبِي بَكْرٍ فَدَعَاهُ فَخَرَجَ إِلَيْهِ ثُمَّ مَرَّ بِعُمَرَ فَدَعَاهُ فَخَرَجَ إِلَيْهِ فَانْطَلَقَ حَتَّى دَخَلَ حَائِطًا لِبَعْضِ الْأَنْصَارِ فَقَالَ لِصَاحِبِ الْحَائِطِ: «أَطْعِمْنَا بُسْرًا» فَجَاءَ بِعِذْقٍ فَوَضَعَهُ فَأَكَلَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَأَصْحَابُهُ ثُمَّ دَعَا بِمَاءٍ بَارِدٍ فَشَرِبَ فَقَالَ: «لَتُسْأَلُنَّ عَنْ هَذَا النَّعِيمِ يَوْمَ القيامةِ» قَالَ: فَأخذ عمر العذق فَضرب فِيهِ الْأَرْضَ حَتَّى تَنَاثَرَ الْبُسْرُ قَبْلَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ثُمَّ قَالَ: يَا رَسُول الله إِنَّا لمسؤولونَ عَنْ هَذَا يَوْمَ الْقِيَامَةِ؟ قَالَ: «نَعَمْ إِلَّا مِنْ ثَلَاثٍ خِرْقَةٍ لَفَّ بِهَا الرَّجُلُ عَوْرَتَهُ أَوْ كِسْرَةٍ سَدَّ بِهَا جَوْعَتَهُ أَوْ حُجْرٍ يتدخَّلُ فِيهِ مَنِ الْحَرِّ وَالْقُرِّ» . رَوَاهُ أَحْمَدُ وَالْبَيْهَقِيُّ فِي «شعب الْإِيمَان» . مُرْسلا