All current versions of this song's chord chart are not actually Ascend the Hill's 
version of the song,
so I made this so that people could genuinely play Ascend the Hill's version of this 
song, as it is
one of the most beautiful reworked hymns I have ever heard.

Rock of Ages – Ascend the Hill
Standard Tuning – Capo on 4th fret

G (3,2,0,0,3,3)
Make sure you have your finger on the 3rd fret of the B string.
C2 (X,3,2,0,3,3)
This is the same as the G chord, but with your top two fingers moved down a string.
D/F# (2,0,0,2,3,3)
Your pinky and ring finger should be in the same place as it was in the G and C2 chord.
C (X,3,2,0,1,0) or (3,3,2,0,1,0)
Adding the 3rd fret on the low E string makes it sound slightly more minor, which is 
good for this song.
D4 (X,5,4,0,3,X) or (5,5,4,0,3,X)
This is the same as the C chord, but moving all your fingers up 2 frets. Try to mute the 
high E string.
Em (0,7,5,0,0,0) or (7,7,5,0,0,0) or (0,2,2,0,0,0)
Personally I like the sound of playing the Em chord higher in this song, but you can 
play it normally.

D/F#    G     C2       G
Rock of Ages, cleft for me,
       G    D4      Em
Let me hide myself in thee.
    D4               C
Let the water and the blood,
         D4                  C
From thy wounded side which flowed,
D/F#  G       C2     G
Be of sin the double cure,
          G    D4           C
Save from wrath and make me pure.

D/F#    G      C2    G
Not the labors of my hands
        G  D4         Em
Can fulfill thy law's demands.
          D4             C
Could my zeal no respite know,
          D4             C
Could my tears forever flow,
D/F#      G         C2   G
These for sin could not atone.
          G    D4        C
Thou must save, and thou alone.

D/F#    G     C2     G
Nothing in my hand I bring,
       G  D4           Em
Simply to thy cross I cling.
       D4                C
Naked, come to thee for dress,
          D4                C
Helpless, look to thee for grace,
D/F#     G     C2       G
Foul, I to thy fountain fly,
         G   D4       Em
Wash me, Savior, or I die.
         G   D4       Em
Wash me, Savior, or I die.
         G   D4        C
Wash me, Savior, or I die.

D/F#     G        C2      G
While I draw this fleeting breath,
        G    D4             Em
When my eyes shall close in death,
       D4                C
When I rise to worlds unknown,
       D4               C
And behold thee on the throne,
C       G     C        G
Rock of Ages, cleft for me,
       G   D4         Em
Let me hide myself in thee.
       G   D4         Em
Let me hide myself in thee.
       G   D4         C
Let me hide myself in thee.