Sawda bint Zama went out at night, and Umar saw her and recognized her. He said, "By Allah, Sawda, you cannot hide yourself from us."She returned to the Prophet ﷺ and mentioned this to him. He was in my chamber having his evening meal, with a bone in his hand. Then revelation came down upon him, and when it lifted, he was saying, "You have been permitted to go out for your needs."
خرجت سودة بنت زمعة ليلا، فرآها عمر فعرفها، فقال: إنك والله يا سودة ما تخفين علينا، فرجعت إلى النبي ﷺ فذكرت ذلك له، وهو في حجرتي يتعشى، وإن في يده لعرقا فأنزل عليه، فرفع عنه، وهو يقول: قد أذن لكن أن تخرجن لحوائجكن.
Bukhari narrated it in the Book of Marriage (5237) via Ali bin Mushir, and Muslim narrated it in the Book of Greetings (17:2170) via Abu Usama, both of them from Hisham bin Urwa, from his father, from Ayesha, and she related it, and the wording given here is Bukhari's.