Messenger of Allah ﷺ said, "When Khosrau perishes, there will be no (more) Khosrau after him, and when Caesar perishes, there will be no more Caesar after him. By Him in Whose Hands Muhammad's life is, you will spend the treasures of both of them in Allah's Cause."
أَنَّهُ قَالَ قَالَ رَسُولُ اللَّهِ ﷺ إِذَا هَلَكَ كِسْرَى فَلاَ كِسْرَى بَعْدَهُ وَإِذَا هَلَكَ قَيْصَرُ فَلاَ قَيْصَرَ بَعْدَهُ وَالَّذِي نَفْسُ مُحَمَّدٍ بِيَدِهِ لَتُنْفِقُنَّ كُنُوزَهُمَا فِي سَبِيلِ اللَّهِ