The Prophet ﷺ said, "If Caesar is ruined, there will be no Caesar after him; and if Khosrau is ruined, there will be no Khosrau, after him; and, by Him in Whose Hand my soul is, surely you will spend their treasures in Allah's Cause."
عَنِ النَّبِيِّ ﷺ قَالَ إِذَا هَلَكَ قَيْصَرُ فَلاَ قَيْصَرَ بَعْدَهُ وَإِذَا هَلَكَ كِسْرَى فَلاَ كِسْرَى بَعْدَهُ وَالَّذِي نَفْسِي بِيَدِهِ لَتُنْفَقَنَّ كُنُوزُهُمَا فِي سَبِيلِ اللَّهِ