(91) CHAPTER. To cast a look at the Imam during As-Salat (the prayer).
Narrated Abu Ma`mar: We asked Khabbab whether Allah's Apostle used to recite (the Qur'an) in the Zuhr and the `Asr prayers. He replied in the affirmative. We said, How did you come to know about it? He said, By the movement of his beard.
Authentic