Chapter on the need to refer to the book and Sunnah
Al-Kāfi|Volume 1|Book 2|Chapter 20
4ـ عَلِيٌّ عَنْ مُحَمَّدِ بْنِ عِيسَى عَنْ يُونُسَ عَنْ حَمَّادٍ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ السَّلام) قَالَ سَمِعْتُهُ يَقُولُ مَا مِنْ شَيْءٍ إِلا وَفِيهِ كِتَابٌ أَوْ سُنَّةٌ.
4. Ali has narrated from Muhammad ibn 'Isa from Yunus from Hammad from abu ‘Abdallah عليه السلام who said: 'I heard him say, “There is nothing except that is has a Book or Sunnah (prophetic tradition)”'.
- Mirʾāt al-ʿUqūl fī Sharḥ Akhbār Āl al-Rasūl (1/204)
- Ṣaḥīḥ al-Kāfī