al-Sharif al-Radi (d. 406 AH) · Thaqalayn library edition, reproduced verbatim
٤٧٧. وَقَالَ (عليه السلام): أَشَدُّ الذُّنُوبِ مَا اسْتَخَفَّ بِهِ صَاحِبُهُ.
477. Amīr al-mu’minīn, peace be upon him, said: The worst sin is that which the committer takes lightly.
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