An-Nahl 16:106

مَن كَفَرَ بِٱللَّهِ مِنۢ بَعْدِ إِيمَٰنِهِۦٓ إِلَّا مَنْ أُكْرِهَ وَقَلْبُهُۥ مُطْمَئِنٌّۢ بِٱلْإِيمَٰنِ وَلَٰكِن مَّن شَرَحَ بِٱلْكُفْرِ صَدْرًۭا فَعَلَيْهِمْ غَضَبٌۭ مِّنَ ٱللَّهِ وَلَهُمْ عَذَابٌ عَظِيمٌۭ

Any one who, after accepting faith in Allah, utters Unbelief,- except under compulsion, his heart remaining firm in Faith - but such as open their breast to Unbelief, on them is Wrath from Allah, and theirs will be a dreadful Penalty.