Al-Mutaffifin • BN-TAFSEER-IBN-E-KASEER
﴿ كَلَّا ۖ بَلْ ۜ رَانَ عَلَىٰ قُلُوبِهِم مَّا كَانُوا۟ يَكْسِبُونَ ﴾
“Nay, but their hearts are corroded by all [the evil] that they were wont to do!”
Please check ayah 83:17 for complete tafsir.