Musannaf Ibn Abi Shaybah

Hazrat Amr bin Saeed says that Hazrat Abu Aliah once entered the mosque, and he was wearing a cap made of fox skin on his head. When he began to pray, he took off this cap and placed it in his sleeve. When he completed the prayer, I asked him, "Why did you take off your cap and put it in your sleeve?" He replied, "I did not like to pray in it, nor was I willing to leave it aside lest it be stolen. Therefore, I put it in my sleeve."