You always see the first part. It’s not offensive or strident. It’s cool and ironic. It doesn’t require you to know God is the Father of the Son Jesus and that you must believe in Him to gain that serenity.
Here’s the “rest of the story”:
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;
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.