Sahih Muslim 3512
صحيح مسلم#3512SahihIbn Umar (Allah be pleased with them) reported Allah's Messenger (may be upon him) having said this:Accept the feast, when you are invited
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 16:115