Al-Kāfi - Volume 2 > Temptation and Soul’s Tale Telling
Hadith #1

1ـ الْحُسَيْنُ بْنُ مُحَمَّدٍ عَنْ مُعَلَّى بْنِ مُحَمَّدٍ عَنِ الْوَشَّاءِ عَنْ مُحَمَّدِ بْنِ حُمْرَانَ قَالَ سَأَلْتُ أَبَا عَبْدِ الله (عَلَيهِ السَّلام) عَنِ الْوَسْوَسَةِ وَإِنْ كَثُرَتْ فَقَالَ لا شَيْ‏ءَ فِيهَا تَقُولُ لا إِلَهَ إِلا الله.

1. Al-Husayn ibn Muhammad has narrated from Mu’alla ibn Muhammad from al- Washsha’ from Muhammad ibn Humran who has said the following: “Once I asked abu ‘Abd Allah (a.s.) ‘What if temptation (soul’s tale telling) becomes a great deal.’ The Imam said, ‘There is nothing in it. Say, ‘No one deserves to be worshipped except Allah.’”