Imam Ja‘far al-Ṣadiq (as): Indeed, Allah has revealed in the Quran explanation for all things. By Allah, He has not left out anything in the Quran which His servants would need, so that no servant would say: If only this was revealed in the Qur'an. [So nothing needs clarification] except that Allah has revealed it in the Qur'an. al-Kāfī