This is in standard tuning. I've been playing this on piano along with the album... so 
certainly in the right key.

     Am                           Em
Dear Prodigal, you are my son and I
    F                                  C     G
Supplied you not your spirit, but your shape
    Am                                Em
All Eden's wealth arrayed before your eyes
  F                          G     Em
I fathomed not you wanted to escape

    Am                          Em
And though I only ever gave you love
     F                               C   G
Like every child you've chosen to rebel
   G                                       Am
Uprooted flowers and filled the holes with blood
    Dm                                G
Ask not for whom they toll the solemn bells

  C                            Em
A Child Of Dust, to mother now return
    Am                            G
For every seed must die before it grows
    F                                    C
And though above, the world may toil and turn
   G                               G7
No prying spade will find you here below

    C                   G                F
Now safe beneath their wisdom and their feet
     C                  G            F
Here I will teach you truly how to sleep