For Everything There Is a Season
I don't like nitpicking, but it's "The B[b:cf09686dda] y[/b:cf09686dda]rds", not the Birds.

And the song wasn't written by them, it was written by folk singer Pete Seeger in 1954 (though the Byrds' version is far better known).
It's adapted from the book of Ecclesiastes, which occupies a unique position in the Bible due to its prevalent sense of pessimism and absence of God's intervention in our world. If you're looking for a book in the Bible which says that despite of the fact that the light at the end of the tunnel always is the train, life is worth living - here you go.
Therefore, although it's most likely just coincidental, you can read the following as a motto for the whole show:
For every thing there is a season,
and a time for every purpose under the heaven:
A time to be born, and a time to die;
A time to plant, and a time to pluck up that which is planted;
A time to kill, and a time to heal;
A time to break down, and a time to build up;
A time to weep, and a time to laugh;
A time to mourn, and a time to dance;
A time to cast away stones, and a time to gather stones together;
A time to embrace, and a time to refrain from embracing;
A time to get, and a time to lose;
A time to keep, and a time to cast away;
A time to rend, and a time to sew;
A time to keep silence, and a time to speak;
A time to love, and a time to hate;
A time of war, and a time of peace.
(Ecclesiastes 1:3)