Hadith 1111:19
Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from Makhul, from Abu Sa‘id, who said: I saw Abu Rafi‘ come to al-Hasan ibn ‘Ali while he was praying, and he had tied his hair back. He loosened it—or forbade him from that—and said: "The Messenger of Allah (peace and blessings of Allah be upon him) saw a man praying while he had tied his hair back, so he forbade him." Or he said: "The Messenger of Allah (peace and blessings of Allah be upon him) forbade that a man should pray while he has tied his hair back."
حدثنا محمد بن جعفر، حدثنا شعبة، عن مخول، عن أبي سعد، قال: رأيت أبا رافع جاء إلى الحسن بن علي وهو يصلي، قد عقص شعره، فأطلقه - أو نهاه عن ذلك - وقال: إن رسول الله صلى الله عليه وسلم رأى رجلا يصلي وقد عقص رأسه، فنهاه أو قال: نهى رسول الله صلى الله عليه وسلم أن يصلي الرجل وهو عاقص شعره "،