Calamities that strike one’s religion are like illnesses that strike the body. Some bodily afflictions are mild—such as a light cold or a minor headache. Likewise, there are minor calamities in religion, like committing certain sins. Then there are ruinous calamities in religion—kufr (disbelief), shirk (associating partners with Allah), and shakk (doubt) and the like—each of which is as destructive to faith as death is to the body. For that reason you ask Allah not to make your trial occur in your religion. As for calamities that fall short of harming the faith, they are relatively easy to bear, for the truly afflicted is the one who is deprived of reward. We ask Allah for well-being.
You also say, “Do not make this world our greatest concern or the limit of our knowledge, and do not, on account of our sins, place over us one who shows us no mercy.” So do not let the life of this world be our chief worry; instead, let the Hereafter be our paramount concern. Yet we should not neglect our allotted share of worldly life, for every person needs something of this world. Still, the world must never become his overriding worry or the extent of his knowledge. Rather, he should ask Allah to make the sum of his knowledge the knowledge of the Hereafter. Worldly knowledge and all that pertains to it—no matter how great—will inevitably vanish. A person might be an expert in medicine, astronomy, geography, or any of the worldly sciences, yet all such learning will fade and perish. What truly counts is the knowledge of the Sacred Law, the knowledge of the Hereafter—that is what matters.
“And do not give power over us one who shows us no mercy”—do not set over us anyone of Your creation who would be merciless toward us; indeed, even one who might show us mercy—do not set anyone over us, but