Reinhold Neibuhr (1892–1971), a theologian and an ethicist wrote the ground-breaking Serenity Prayer – a version Alcoholics Anonymous uses in their Twelve Step Program:
God grant me the serenity
To accept the things I cannot change;
Courage to change the things I can;
And wisdom to know the difference.
Living one day at a time;
Enjoying one moment at a time;
Accepting hardships 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;
So that I may be reasonably happy in this life
And supremely happy with Him
Forever and ever in the next.