Anas bin Malik reported,

I am the most knowledgeable of people regarding the verse of the veil. Ubayy bin Kaab used to ask me about it.The Messenger of Allah ﷺ became a bridegroom one morning to Zaynab bint Jahsh, whom he had married in Medina. He invited the people to a meal after the day had grown bright. The Messenger of Allah ﷺ sat down, and some men sat with him after the rest of the people had risen, until the Messenger of Allah ﷺ himself stood up and walked away, and I walked along with him until he reached the door of Ayesha's room. Then he thought they had left, so he returned, and I returned with him, but there they were, still sitting in their places. He turned back again, and I returned with him a second time until he reached the door of Ayesha's room. He went back, and I went back with him, and this time they had risen. He then drew a curtain between me and himself, and the verse of the veil was revealed.

Bukhari 5466

Sahih

حدثني عبد الله بن محمد حدثنا يعقوب بن إبراهيم قال حدثني أبي عن صالح عن ابن شهاب أن

أنسا قال

أنا أعلم الناس بالحجاب كان أبي بن كعب يسألني عنه أصبح رسول الله ﷺ عروسا بزينب بنت جحش وكان تزوجها بالمدينة فدعا الناس للطعام بعد ارتفاع النهار فجلس رسول الله ﷺ وجلس معه رجال بعد ما قام القوم حتى قام رسول الله ﷺ فمشى ومشيت معه حتى بلغ باب حجرة عائشة ثم ظن أنهم خرجوا فرجعت معه فإذا هم جلوس مكانهم فرجع ورجعت معه الثانية حتى بلغ باب حجرة عائشة فرجع ورجعت معه فإذا هم قد قاموا فضرب بيني وبينه سترا وأنزل الحجاب

البخاري 5466صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Bukhari
Book
Foods
Chapter
His saying, "And when you have eaten, disperse"
Numbering
Darussalam 5466
Bukhari 5466