Sahih al-Bukhari 4632
Sahih al-Bukhari · Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)) · The Statement of Allah: "They are those whom Allah had guided. So, follow their guidance..." (V.6:90)
Narrated Mujahid:
حَدَّثَنِي إِبْرَاهِيمُ بْنُ مُوسَى ، أَخْبَرَنَا هِشَامٌ ، أَنَّ ابْنَ جُرَيْجٍ ، أَخْبَرَهُمْ قَالَ أَخْبَرَنِي سُلَيْمَانُ الأَحْوَلُ ، أَنَّ مُجَاهِدًا ، أَخْبَرَهُ أَنَّهُ، سَأَلَ ابْنَ عَبَّاسٍ أَفِي " ص " سَجْدَةٌ فَقَالَ نَعَمْ. ثُمَّ تَلاَ {وَوَهَبْنَا} إِلَى قَوْلِهِ {فَبِهُدَاهُمُ اقْتَدِهْ} ثُمَّ قَالَ هُوَ مِنْهُمْ. زَادَ يَزِيدُ بْنُ هَارُونَ وَمُحَمَّدُ بْنُ عُبَيْدٍ وَسَهْلُ بْنُ يُوسُفَ عَنِ الْعَوَّامِ عَنْ مُجَاهِدٍ قُلْتُ لاِبْنِ عَبَّاسٍ فَقَالَ نَبِيُّكُمْ صلى الله عليه وسلم مِمَّنْ أُمِرَ أَنْ يَقْتَدِيَ بِهِمْ.
That he asked Ibn `Abbas, "Is there a prostration Surat-al-Sa`d?" (38.24) Ibn `Abbas said, "Yes," and then recited: "We gave...So follow their guidance." (6.85,90) Then he said, "He (David ) is one them (i.e. those prophets)." Mujahid narrated: I asked Ibn `Abbas (regarding the above Verse). He said, "Your Prophet (Muhammad) was one of those who were ordered to follow them."