63 : 3
ذَٰلِكَ بِأَنَّهُمۡ ءَامَنُواْ ثُمَّ كَفَرُواْ فَطُبِعَ عَلَىٰ قُلُوبِهِمۡ فَهُمۡ لَا يَفۡقَهُونَ
That is because they believed, and then disbelieved; therefore their hearts are sealed, so they understand not.
Ayah 3 of المُنَافِقُونَ (63 : 3). This page carries the verse in the Uthmani script with a translation of its meaning, at a stable URL that can be cited on its own.
ذَٰلِكَ بِأَنَّهُمۡ ءَامَنُواْ ثُمَّ كَفَرُواْ فَطُبِعَ عَلَىٰ قُلُوبِهِمۡ فَهُمۡ لَا يَفۡقَهُونَ
That is because they believed, and then disbelieved; therefore their hearts are sealed, so they understand not.