Adapun perkataannya dalam tafsir Al-Qur'an, maka jumlahnya banyak.

As for his words in commentary on the Qur’an, there are many.

Ibn Sa°d meriwayatkan bahawa cAli berkata, "Demi Allah, tidak ada satu ayat pun yang diturunkan tanpa aku mengetahui tentang apa ia diturunkan, di mana ia diturunkan, dan tentang siapa ia diturunkan. Tuhanku telah mengurniakan kepadaku hati yang sangat bijak dan lidah yang benar serta fasih." Ibn Sa°d dan lain-lain meriwayatkan bahawa Abu't-Tufayl berkata: cAli berkata, "Tanyalah kepadaku tentang Kitab Allah, kerana tidak ada satu ayat pun melainkan aku tahu sama ada ia diturunkan pada waktu malam atau pada waktu siang, di dataran atau di gunung." Ibn Abi Dawud meriwayatkan bahawa Muhammad ibn Sirin berkata: Apabila Nabi ﷺ wafat, cAli lambat untuk memberikan baiah kepada Abu Bakr. Abu Bakr menemui beliau dan berkata, "Adakah engkau tidak menyukai (pemerintahan) aku?" Beliau menjawab, "Tidak, tetapi aku telah bersumpah untuk tidak memakai selendangku, kecuali untuk solat, sehingga aku telah mengumpulkan Al-Qur'an." Mereka mendakwa bahawa beliau menulisnya mengikut susunan penurunannya. Muhammad (ibn Sirin) lalu berkata, "Jika kitab itu dapat ditemui, nescaya terdapat ilmu di dalamnya."

Ibn Sa°d narrated that cAli said, ‘By Allah, an ayah has not been revealed without me knowing about what it was revealed, where it was revealed, and about whom it was revealed. My Lord has given me a very intelligent heart and a true and articulate tongue.’ Ibn Sacd and others narrated that Abu’t-Tufayl said: cAli said, Ask me about the Book of Allah, because there is no ayah but that I know whether it was revealed at night or in daytime, on the plain or in the mountain.’ Ibn Abi Dawud narrated that Muhammad ibn Sirin said: When the Prophet, may Allah bless him and grant him peace, died, cAli was slow to pledge allegiance to Abu Bakr. Abu Bakr met him and said, ‘Do you dislike my (having the) authority?’ He said, ‘No, but I have sworn not to don my mantle, except for the prayer, until I have collected together the Qur’an.’ They claimed that he wrote it in the order of its revelation. Muhammad (ibn Sirin) thus said, ‘If that book were come across, there would be knowledge in it.’