Al 'Imran, 90 Ayah
3:90
إِنَّ ٱلَّذِينَ كَفَرُواْ بَعۡدَ إِيمَٰنِهِمۡ ثُمَّ ٱزۡدَادُواْ كُفۡرٗا لَّن تُقۡبَلَ تَوۡبَتُهُمۡ وَأُوْلَٰٓئِكَ هُمُ ٱلضَّآلُّونَ ٩٠
'Inna Al-Ladhīna Kafarū Ba`da 'Īmānihim Thumma Azdādū Kufrāan Lan Tuqbala Tawbatuhum Wa 'Ūlā'ika Humu Ađ-Đāllūna
Indeed, those who reject the message after their belief and then increase in disbelief - never will their [claimed] repentance be accepted, and they are the ones astray.