Al-Qurtubi reported: Malik ibn Dinar, may Allah have mercy on him, said, “A servant is not struck by a greater punishment than having a hard heart. Allah is not angry with people but that he removes mercy from their hearts.”
Source: Tafsīr al-Qurṭubī 39:22
عن القرطبي قَالَ قَالَ مَالِك بْن دِينَارٍ رحمه الله مَا ضُرِبَ عَبْدٌ بِعُقُوبَةٍ أَعْظَمَ مِنْ قَسْوَةِ قَلْبٍ وَمَا غَضِبَ اللَّهُ عَلَى قَوْمٍ إِلَّا نَزَعَ الرَّحْمَةَ مِنْ قُلُوبِهِمْ
39:22 الجامع لأحكام القرآن سورة الزمر قوله تعالى أفمن شرح الله صدره للإسلام