Al-Kāfi

Hadith 1430
certaintyhellfire
5ـ الْحُسَيْنُ بْنُ مُحَمَّدٍ عَنْ أَحْمَدَ بْنِ إِسْحَاقَ عَنْ بَكْرِ بْنِ مُحَمَّدٍ عَنْ أَبِي عَبْدِ الله (عَلَيهِ السَّلام) قَالَ إِنَّ الشَّكَّ وَالْمَعْصِيَةَ فِي النَّارِ لَيْسَا مِنَّا وَلا إِلَيْنَا.
5. Al-Husayn ibn Muhammad has narrated from Ahmad ibn Ishaq from Bakr ibn Muhammad from Abu ‘Abdillah (a.s.) who has said the following: “Abu ‘Abd Allah (a.s.) has said, ‘Doubts and disobedience are in the fire. It (doubt or people having doubts) is not from us nor is it directed to us.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī