Al-Kāfi
Hadith 139810ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدِ بْنِ عِيسَى عَنِ ابْنِ مَحْبُوبٍ عَنْ عَبْدِ الله بْنِ سِنَانٍ عَنْ أَبِي عَبْدِ الله (عَلَيهِ السَّلام) قَالَ مَنْ شَكَّ فِي الله وَفِي رَسُولِهِ (صَلَّى اللهُ عَلَيْهِ وآلِه) فَهُوَ كَافِرٌ.
10. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad ibn ‘Isa from ibn Mahbub from ‘Abd Allah ibn Sinan from Abu ‘Abdillah (a.s.) who has said the following: “Abu ‘Abd Allah (a.s.) has said, ‘Whoever doubts Allah and the Messenger of Allah is an unbeliever.’”