Musannaf Ibn Abi Shayba 3:3899

Al-Fadl ibn Dukayn narrated to us, he said: Isma'il ibn 'Abd al-Malik narrated to us, he said: Yunus ibn Khabbab narrated to me, from Mujahid, who said: I used to lead my master, al-Sa'ib, while he was blind. He would say to me, "O Mujahid, has the sun declined?" So when I said, "Yes," he would stand and pray the Dhuhr prayer.