Mujahid narrates: I asked Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both), "From where did you derive the ruling of the prostration of recitation in Surah Sad?" He recited this verse before me: "Among his descendants are Muslims: Dawud, Sulaiman, and Ayyub." He recited this verse up to: "These are the ones whom Allah has guided, so follow their guidance." Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: Sayyiduna Dawud (peace be upon him) performed prostration at this place, and for this reason, the Noble Prophet (peace and blessings be upon him) also performed prostration (at this verse).