Narrated Abu Sa’id Al Khudri :The Messenger of Allah (ﷺ) forbade fasting on two days, al-Fitr (breaking the fast of Ramadan) and al-Adha (the day of sacrifice), and wearing a tight single garment the raising of which discloses private parts, and sitting with one's legs drawn up and wrapped in one's garment, and forbade praying at two hours, after the Fajr prayer and after the Asr prayer

English translation · Sunan Abu Dawud