Jami` at-Tirmidhi 3304

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.”