Sahih Muslim 1663
Sahih Muslim · Book 27: The Book of Oaths · Feeding a slave what one eats and clothing him as one clothes oneself, and not burdening him with more than he bear
Abu Huraira reported Allah's Messenger (ﷺ) as saying:
وَحَدَّثَنَا الْقَعْنَبِيُّ ، حَدَّثَنَا دَاوُدُ بْنُ قَيْسٍ ، عَنْ مُوسَى بْنِ يَسَارٍ ، عَنْ أَبِي هُرَيْرَةَ ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِذَا صَنَعَ لأَحَدِكُمْ خَادِمُهُ طَعَامَهُ ثُمَّ جَاءَهُ بِهِ وَقَدْ وَلِيَ حَرَّهُ وَدُخَانَهُ فَلْيُقْعِدْهُ مَعَهُ فَلْيَأْكُلْ فَإِنْ كَانَ الطَّعَامُ مَشْفُوهًا قَلِيلاً فَلْيَضَعْ فِي يَدِهِ مِنْهُ أُكْلَةً أَوْ أُكْلَتَيْنِ " . قَالَ دَاوُدُ يَعْنِي لُقْمَةً أَوْ لُقْمَتَيْنِ .
When the slave of anyone amongst you prepares food for him and he serves him after having sat close to (and undergoing the hardship of) heat and smoke, he should make him (the slave) sit along with him and make him eat (along with him), and if the food seems to run short, then he should spare some portion for him (from his own share) - (another narrator) Dawud said:" i. e. a morsel or two". 4097