The Prophet ﷺ said, "By Him in Whose Hands my life is! Were it not for some men amongst the believers who dislike to be left behind me and whom I cannot provide with means of conveyance, I would certainly never remain behind any Sariya' (army-unit) setting out in Allah's Cause. By Him in Whose Hands my life is! I would love to be martyred in Allah's Cause and then get resurrected and then get martyred, and then get resurrected again and then get martyred and then get resurrected again and then get martyred.  

سَمِعْتُ النَّبِيَّ ﷺ يَقُولُ وَالَّذِي نَفْسِي بِيَدِهِ لَوْلاَ أَنَّ رِجَالاً مِنَ الْمُؤْمِنِينَ لاَ تَطِيبُ أَنْفُسُهُمْ أَنْ يَتَخَلَّفُوا عَنِّي وَلاَ أَجِدُ مَا أَحْمِلُهُمْ عَلَيْهِ مَا تَخَلَّفْتُ عَنْ سَرِيَّةٍ تَغْزُو فِي سَبِيلِ اللَّهِ وَالَّذِي نَفْسِي بِيَدِهِ لَوَدِدْتُ أَنِّي أُقْتَلُ فِي سَبِيلِ اللَّهِ ثُمَّ أُحْيَا ثُمَّ أُقْتَلُ ثُمَّ أُحْيَا ثُمَّ أُقْتَلُ ثُمَّ أُحْيَا ثُمَّ أُقْتَلُ  

The Prophet ﷺ delivered a sermon and said, "Zaid took the flag and was martyred, and then Jaʿfar took the flag and was martyred, and then ʿAbdullah bin Rawaha took the flag and was martyred too, and then Khalid bin Al-Walid took the flag though he was not appointed as a commander and Allah made him victorious." The Prophet ﷺ further added, "It would not please us to have them with us." Aiyub, a sub-narrator, added, "Or the Prophet, shedding tears, said, 'It would not please them to be with us.'"  

خَطَبَ النَّبِيُّ ﷺ فَقَالَ أَخَذَ الرَّايَةَ زَيْدٌ فَأُصِيبَ ثُمَّ أَخَذَهَا جَعْفَرٌ فَأُصِيبَ ثُمَّ أَخَذَهَا عَبْدُ اللَّهِ بْنُ رَوَاحَةَ فَأُصِيبَ ثُمَّ أَخَذَهَا خَالِدُ بْنُ الْوَلِيدِ عَنْ غَيْرِ إِمْرَةٍ فَفُتِحَ لَهُ وَقَالَ مَا يَسُرُّنَا أَنَّهُمْ عِنْدَنَا قَالَ أَيُّوبُ أَوْ قَالَ مَا يَسُرُّهُمْ أَنَّهُمْ عِنْدَنَا وَعَيْنَاهُ تَذْرِفَانِ