What is said upon the calamity of the passing of the Messenger, may Allah’s prayers and peace be upon him, and is it permissible to say concerning it: "O Allah, reward me in my calamity and compensate me with something better than it"?

The calamity that befell Muslims with the Messenger—may Allah's prayers and peace be upon him—is unlike any other calamity; it is the greatest of all calamities. No one better than him will come after him, nor did anyone better than him come before him, as he—may Allah's prayers and peace be upon him—said: "If any of you is afflicted by a calamity, let him remember his calamity by me, for it is the greatest of calamities." Therefore, the phrase "and replace it with something better" is said concerning a calamity other than his—may Allah's prayers and peace be upon him.