Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:2:10 –

In their hearts is disease, so Allah has increased their disease; and for them is a painful punishment because they ˹habitually˺ used to lie.  

In their hearts is a sickness: doubt and hypocrisy, which ails their hearts, debilitating them; and God has increased their sickness with what He has revealed in the Qur’ān, since they disbelieve it; and there awaits them a painful chastisement because they used to lie (read yukadhdhibūn to imply ˹that they used to call˺ the Prophet of God ˹a liar˺, or yakdhibūn to imply their ˹mendacity when˺ saying ‘we believe’).
القرآن:٢:١٠ –

فِي قُلُوبِهِمْ مَرَضٌ فَزَادَهُمُ اللَّهُ مَرَضًا ۖ وَلَهُمْ عَذَابٌ أَلِيمٌ بِمَا كَانُوا يَكْذِبُونَ  

{في قلوبهم مرض} شك ونفاق فهو يمرض قلوبهم أي يضعفها {فزادهم الله مرضاً} بما أنزله من القرآن لكفرهم به {ولهم عذاب أليم} مؤلم {بما كانوا يُكذّبوِن} بالتشديد أي: نبي الله، وبالتخفيف أي قولهم آمنا.