“Lord, grant me the strength to change the things I can, the serenity to deal with the things I cannot change, and the wisdom to know the difference.” – Saint Francis of Assisi (or Augustine, or Thomas Aquinas, etc.)

This is actually known, in its various forms, as the Serenity Prayer and was made famous by the Alcoholics Anonymous in 1941. It is also generally believed to have been written by Reinhold Niebuhr, a Reformed (Calvinist) theologian. Others attribute it to his colleague, Winnifred Wygal.

https://en.wikipedia.org/wiki/Serenity_Prayer