Awesome song.  Knowing By the Tree this song may be tuned down a half-step, 
but I just slapped a capo on the first fret to make is simple.

Intro/Verse:  D/F#  D (5th fret D barred)

Chorus:  D (regular) G
         Bm  A  G  (Where he says, Jesus washed, Jesus washed)

Verse 2:  D/F#  D

Chorus:  D  G
         Bm  A  G

Bridge (Instrumental):  D   G

That's it and super easy.