That is not at all (the case); rather (the fact is that the evil deeds) which they earned have rusted their hearts. (The Revelations, therefore, do not move their hearts.
"No (they are mistaken), but the things they have done have put rust on their hearts."
Sayyed Abbas Sadr-Ameli
Nay, Rather what they used to do has put rust upon their hearts
Al-muntakhab fi tafsir al-Qur'an al-Karim
No, but what deafened their hearts' ears and made them irresponsive was the blight which their hearts acquired through their ill deeds and woeful story