Nahj al-Balāgha
Hadith 2220۳۸۸. وَقَالَ (عليه السلام): أَلَا وإِنَّ مِنَ الْبَلاَءِ الْفَاقَةَ وَأَشَدُّ مِنَ الْفَاقَةِ مَرَضُ الْبَدَنِ، وَأشدُّ مِنْ مَرَضِ الْبَدَنِ مَرَضُ الْقَلْبِ.
388. Amīr al-mu’minīn, peace be upon him, said: Beware that destitution is a calamity, but worse than destitution is ailment of the body, while worse than bodily ailment is the disease of the heart.