﴿ وَإِنَّ مِنكُمْ لَمَن لَّيُبَطِّئَنَّ فَإِنْ أَصَٰبَتْكُم مُّصِيبَةٌۭ قَالَ قَدْ أَنْعَمَ ٱللَّهُ عَلَىَّ إِذْ لَمْ أَكُن مَّعَهُمْ شَهِيدًۭا ﴾

“And, behold, there are indeed among you such as would lag behind, and then, if calamity befalls you, say, "God has bestowed His favour upon me in that I did not accompany them."”

2. Seen outwardly, the words of the verse 72 (... وَإِنَّ مِنكُمْ ) seem to suggest that this too is addressed to the believers, although the characteristics described later on cannot be taken to be those of the believers. Therefore, al-Qurtubi says that they signify hypocrites. Since, they were the ones who used to claim being Muslims, at least outwardly. This is why they have been identified as a group from among the believers.