﴿ إِنَّمَا يَسْتَـْٔذِنُكَ ٱلَّذِينَ لَا يُؤْمِنُونَ بِٱللَّهِ وَٱلْيَوْمِ ٱلْءَاخِرِ وَٱرْتَابَتْ قُلُوبُهُمْ فَهُمْ فِى رَيْبِهِمْ يَتَرَدَّدُونَ ﴾

“only those ask thee for exemption who do not [truly] believe in God and the Last Day and whose hearts have become a prey to doubt, so that in their doubting they waver between one thing and another.”

In the second (44) and third (45) verses given there was the difference between believers and hypocrites. Those who believe in Allah Ta` ala truly and staunchly do not pick an occasion like that only to seek desertion from Jihad just for the sake of love for their lives and wealth and go about asking the permission of their prophet to stay back. In fact, this is the behavior of only those who do not believe in Allah and the Day of Judgment (Akhirah), truly and correctly - and, as for Allah, He knows the God-fearing perfectly well.