Abu Hurairah narrated: That a man from the Ansar had a guest spend the night with him, but he did not have anything to eat but his meal and the meal for his children, so he said to his wife: ‘Put the children to sleep, extinguish the torches, and give me whatever you have with you for the guest.’ So this Ayah was revealed: And they give preference over themselves even though they were in need of that.”
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا أَبُو كُرَيْبٍ، حَدَّثَنَا وَكِيعٌ، عَنْ فُضَيْلِ بْنِ غَزْوَانَ، عَنْ أَبِي حَازِمٍ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَجُلاً، مِنَ الأَنْصَارِ بَاتَ بِهِ ضَيْفٌ فَلَمْ يَكُنْ عِنْدَهُ إِلاَّ قُوتُهُ وَقُوتُ صِبْيَانِهِ فَقَالَ لاِمْرَأَتِهِ نَوِّمِي الصِّبْيَةَ وَأَطْفِئِي السِّرَاجَ وَقَرِّبِي لِلضَّيْفِ مَا عِنْدَكِ فَنَزَلَتْ هَذِهِ الآيَةُُ : ( ويؤْثِرُونَ عَلَى أَنْفُسِهِمْ وَلَوْ كَانَ بِهِمْ خَصَاصَةٌ ) هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ .
sunnah.com