Volume 6, Book 60, Number 330:
Narrated Al-Awwam:
I asked Muhajid regarding the prostration in Surat Sad. He said, “Ibn Abbas was asked the same
question and he said, ‘Those are they (the prophets) whom Allah had Guided. So follow their guid –
ance.” (6.90) Ibn ‘Abbas used to perform a prostration (on reading this Sura).

Volume 6, Book 60, Number 331:
Narrated Al-Awwam:
I asked Mujahid regarding the prostration in Surat Sad. He said, “I asked Ibn ‘Abbas, ‘What evid –
ence makes you prostrate?’ He said, “Don’t you recite:–‘And among his progeny, David and So –
lomon..(6.84). Those are they whom Allah had guided. So follow their guidance.’ (6.90) So David was
the one of those prophets whom Prophet (Muhammad) was ordered to follow. David prostrated, so
Allah’s Apostle (Muhammad) performed this prostration too.’