Hadithcore
Sahih Muslim, 1429 i
sahih

Ibn Umar (Allah be pleased with them) reported Allah's Messenger (ﷺ) having said:

When you are invited to a feast (even though it is) the leg of the sheep, you should accept it.

وَحَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى، أَخْبَرَنَا ابْنُ وَهْبٍ، حَدَّثَنِي عُمَرُ بْنُ مُحَمَّدٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ ‏

‏ إِذَا دُعِيتُمْ إِلَى كُرَاعٍ فَأَجِيبُوا ‏

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References2 variants
In-Book Reference
Book 16, Hadith 120
USC-MSA web (English) reference
Book 8, Hadith 3345 (deprecated numbering scheme)