Musnad Ahmad 25:573

Mu'ammal narrated to us, Abu 'Awanah said: Abu Bishr narrated to us, from Sa'id ibn Jubayr, from Ibn 'Abbas, regarding the saying of the Jinn: {And when the servant of Allah stood up calling upon Him, they almost crowded upon him in layers} [Al-Jinn: 19]. He said: "When they saw him praying with his companions, and they were praying with his prayer, and bowing with his bowing, and prostrating with his prostration, they marveled at his companions' obedience to him. So when they returned to their people, they said: 'Indeed, when the servant of Allah—meaning the Prophet, may Allah bless him and grant him peace—stood up calling upon Him, they almost crowded upon him in layers.'"