The original serenity prayer as written by Reinhold Niebuhr goes like this:
God, give me grace to accept with serenity
the things that cannot be changed,
Courage to change the things
which should be changed,
and the Wisdom to distinguish
the one from the other.
Living one day at a time,
Enjoying one moment at a time,
Accepting hardship as a pathway to peace,
Taking, as Jesus did,This sinful world as it is,
Not as I would have it,
Trusting that You will make all things right,
If I surrender to Your will,
So that I may be reasonably happy in this life,
And supremely happy with You forever in the next.
The second, less-known part really points to mindfulness for me. You can’t deal with all the future moments or change the past moments. You can only deal with a single moment at one time. And, hopefully, it will be one of enjoyment.