At-Taubah - 9:45

إِنَّمَا يَسْتَأْذِنُكَ الَّذِينَ لاَ يُؤْمِنُونَ بِاللّهِ وَالْيَوْمِ الآخِرِ وَارْتَابَتْ قُلُوبُهُمْ فَهُمْ فِي رَيْبِهِمْ يَتَرَدَّدُونَ
[9:45]
They only ask leave of you who do not believe in Allah and the latter day and their hearts are in doubt, so in their doubt do they waver.
Only those ask thee for exemption who believe not in Allah and the Last Day, and whose hearts are in doubt, so that they are tossed in their doubts to and fro.
They alone ask leave of thee who believe not in Allah and the Last Day, and whose hearts feel doubt, so in their doubt they waver.