Sahih (Sahih Muslim)
وَحَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا خَالِدُ بْنُ الْحَارِثِ، عَنْ عُبَيْدِ اللَّهِ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِذَا دُعِيَ أَحَدُكُمْ إِلَى الْوَلِيمَةِ فَلْيُجِبْ " . قَالَ خَالِدٌ فَإِذَا عُبَيْدُ اللَّهِ يُنَزِّلُهُ عَلَى الْعُرْسِ .
Ibn 'Umar (Allah be pleased with them) reported Allah's Apostle (ﷺ) as saying:When any one of you is invited to a feast, he should accept. 'Ubaidallah took this feast to be a wedding feast