al-Sharif al-Radi (d. 406 AH) · Thaqalayn library edition, reproduced verbatim
وَاعْلَمْ ـ يَا مُحَمَّدُ بْنَ أَبِي بَكْر ـ أَنِّي قَدْ وَلَّيْتُكَ أَعْظَمَ أَجْنَادِي فِي نَفْسِي أَهْلَ مِصْرَ، فَأَنْتَ مَحْقُوقٌ أَنْ تُخَالِفَ عَلَى نَفْسِكَ، وَأَنْ تُنَافِحَ عَنْ دِينِكَ، وَلَوْ لَمْ يَكُنْ لَكَ إِلَّا سَاعَةٌ مِنَ الدَّهْرِ، وَلَا تُسْخِطِ اللهَ بِرِضَا أَحَدٍ مِنْ خَلْقِهِ، فَإِنَّ فِي اللهِ خَلَفاً مِنْ غَيْرِهِ، وَلَيْسَ مِنَ اللهِ خَلَفٌ فِي غَيْرِهِ.
O’ Muḥammad ibn Abī Bakr, know that I have given you charge of Egypt which is my biggest force. So you are duty-bound to oppose your passions and serve as a shield against your religion even though you may get only an hour in the world; and do not enrage Allāh for pleasing others because (Allāh) is such that He may take the place of others, but others cannot take the place of Allāh.
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