"O you who have believed, do not be like those who disbelieved and said to their brothers when they traveled upon the earth," meaning: for trade, "or went out fighting," meaning: in the military expedition.
Muhammad said: "Guzan" is the plural of "Gazin" (warrior), just as "Qasin" (harsh) is for "Qusan" and "'Afin" (pardoning) is for "'Afun." Al-Hasan said: They are the hypocrites. "And said to their brothers," meaning: their brothers in what the hypocrites manifest of faith: "If they had been with us, they would not have died or been killed." They said this because they have no intention for Jihad. God said: "So that Allah may make that a regret in their hearts." That is because they were fighting against a people who shared their religion, so that is a torment and regret for them.
﴿يَا أَيهَا الَّذِينَ آمَنُوا لَا تَكُونُوا كَالَّذِينَ كَفَرُوا وَقَالُوا لإِخْوَانِهِمْ إِذَا ضَرَبُوا فِي الأَرْض﴾ يَعْنِي: التِّجَارَة ﴿أَوْ كَانُوا غُزًّى﴾ يَعْنِي: فِي الْغَزْو.
قَالَ مُحَمَّد: ﴿غزى﴾ جمع (غَازٍ﴾ مثل: قَاس وقسى، وعاف وَعفى قَالَ الْحسن: هم المُنَافِقُونَ ﴿وَقَالُوا لإخوانهم﴾ يَعْنِي: إخْوَانهمْ فِيمَا يظْهر المُنَافِقُونَ من الْإِيمَان. ﴿لَوْ كَانُوا عِنْدَنَا مَا مَاتُوا وَمَا قتلوا﴾ قَالُوا هَذَا؛ لِأَنَّهُ لَا نِيَّة لَهُم فِي الْجِهَاد. قَالَ الله: ﴿لِيَجْعَلَ اللَّهُ ذَلِكَ حَسْرَةً فِي قُلُوبهم﴾ وَذَلِكَ أَنهم كَانُوا يجاهدون قوما على دينهم، فَذَلِك عَلَيْهِم عَذَاب وحسرة
