Abu Hurairah reported,

The Prophet ﷺ withdrew from his wives. Shuba said, I think he said for a month.Umar bin Khattab came to him while he was in an upper room, lying on a reed mat that had left marks on his back. Umar said, "Messenger of Allah, the kings of Persia drink from vessels of gold and silver, while you are in this state?"The Prophet ﷺ replied, "They have been given their good things in advance during their worldly life."Then the Prophet ﷺ said, "The month is twenty-nine days, like this, and like this, and like this," folding his thumb on the third time.

حدثنا محمد بن جعفر حدثنا شعبة عن داود بن فراهيج قال سمعت

أبا هريرة قال

هجر النبي ﷺ نساءه قال شعبة وأحسبه قال شهرا فأتاه عمر بن الخطاب رضي الله عنه وهو في غرفة على حصير قد أثر الحصير بظهره فقال يا رسول الله كسرى يشربون في الذهب والفضة وأنت هكذا فقال النبي ﷺ إنهم عجلت لهم طيباتهم في حياتهم الدنيا ثم قال النبي ﷺ الشهر تسعة وعشرون هكذا وهكذا وكسر في الثالثة الإبهام