The serenity prayer is one the most beautiful prayers from the Christian tradition. It offers much solace and wisdom. Most people are familiar with the first part, though only a few know the entire prayer, which was an untitled prayer written by the theologian Reinhold Niebuhr in the 1930s.
God, grant me the serenity
to accept the things I cannot change,
courage to change the things I can,
and the wisdom to know the difference.
Living one day at a time,
enjoying one moment at a time,
accepting hardship as the pathway to peace;
taking, as He did, this sinful world as it is,
not as I would have it;
trusting that He will make all things right
if I surrender to His will;
that I may be reasonably happy in this life,
and supremely happy with Him forever
in the next.