لَوْ كَانَ عَرَضًا قَرِيبًا وَسَفَرًا قَاصِدًا لَّاتَّبَعُوكَ وَلَٰكِن بَعُدَتْ عَلَيْهِمُ الشُّقَّةُ ۚ وَسَيَحْلِفُونَ بِاللَّهِ لَوِ اسْتَطَعْنَا لَخَرَجْنَا مَعَكُمْ يُهْلِكُونَ أَنفُسَهُمْ وَاللَّهُ يَعْلَمُ إِنَّهُمْ لَكَاذِبُونَ (42)
(9:42) O Prophet, had there been a prospect of immediate gain and an easy journey, most certainly they would have been quite ready to follow you; but the journey seemed too hard to them. *44 Still they will swear by Allah and say, "Had we been able to go forth, we would certainly have marched along with you"; they are incurring destruction on themselves: for Allah knows well that they are liars.
*44) They felt the journey to Tabuk to be hard because they had to fight with the army of the great and powerful Roman Empire: because they had to journey in the scorching heat of the summer season of the desert: because there was a famine in the country and the new harvest on which they had pinned their hopes, was ready for reaping.