An-Nahl - ১৬:১০৬

مَن كَفَرَ بِاللّهِ مِن بَعْدِ إيمَانِهِ إِلاَّ مَنْ أُكْرِهَ وَقَلْبُهُ مُطْمَئِنٌّ بِالإِيمَانِ وَلَـكِن مَّن شَرَحَ بِالْكُفْرِ صَدْرًا فَعَلَيْهِمْ غَضَبٌ مِّنَ اللّهِ وَلَهُمْ عَذَابٌ عَظِيمٌ
[16:106]
He who disbelieves in Allah after his having believed, not he who is compelled while his heart is at rest on account of faith, but he who opens (his) breast to disbelief-- on these is the wrath of Allah, and they shall have a grievous chastisement.
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.
Whoso disbelieveth in Allah after his belief - save him who is forced thereto and whose heart is still content with the Faith - but whoso findeth ease in disbelief: On them is wrath from Allah. Theirs will be an awful doom.