سنن ابو داؤد #1111

Ya'la b. Shaddad b. Aws said:I came to Mu'awiyah in Jerusalem. He led us in the Friday prayer. I saw that most of the people in the mosque were the Companions of the Prophet (ﷺ). I saw them sitting in ihtiba condition, i.e. sitting on hips erecting the feet and sticking them to the stomach and holding them with hands or tying them with a cloth to the back, while the imam was giving sermon. Abu Dawud said: Ibn 'Umar used to sit in ihtiba position while the imam gave the Friday sermon. Anas b. Malik, Shuraih, Sa'sa'ah b. Sawhan, Sa'id b. al-Musayyib, Ibrahim al-Nakha'i, Makhul, Isma'il, Ismail b. Muhammad b. Sa'd, and Nu'aim b. Sulamah said: There is no harm in sitting in ihtiba position. Abu Dawud said: I do not know whether anyone considered it disapproved except 'Ubadah b. Nasayy