Al-Kāfi

Hadith 988
major-sinstrials-afflictions
29ـ أَحْمَدُ بْنُ مُحَمَّدٍ الْكُوفِيُّ عَنْ عَلِيِّ بْنِ الْحَسَنِ الْمِيثَمِيِّ عَنِ الْعَبَّاسِ بْنِ هِلالٍ الشَّامِيِّ مَوْلىً لأبِي الْحَسَنِ مُوسَى (عَلَيهِ السَّلام) قَالَ سَمِعْتُ الرِّضَا (عَلَيهِ السَّلام) يَقُولُ كُلَّمَا أَحْدَثَ الْعِبَادُ مِنَ الذُّنُوبِ مَا لَمْ يَكُونُوا يَعْمَلُونَ أَحْدَثَ الله لَهُمْ مِنَ الْبَلاءِ مَا لَمْ يَكُونُوا يَعْرِفُونَ.
29. Ahmad ibn Muhammad al-Kufi has narrated from Ali ibn al-Hassan al- Maythami from al-‘Abbas ibn Hilal al-Shami, Mawla of abu al-Hassan Musa (a.s.) who has said the following: “I heard al-Rida (a.s.) saying, ‘Whenever servants commit such sins that they had not committed before, Allah creates a new misfortune against them of which they had no knowledge.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī