(16) باب الأَمْرِ بِإِجَابَةِ الدَّاعِي إِلَى دَعْوَةٍ
Ibn Umar (Allah be pleased withthem) reported Allah's Apostle (ﷺ) having said this:
When any one of you is invited to a wedding feast, he should accept that.
Reference: Sahih Muslim 1429 c
In-book reference: Book 16, Hadith 114
USC-MSA web (English) reference(deprecated numbering scheme): Book 8, Hadith 3339