When playing Peace Like A River, remember not to play an octave and chord on the pickup measure. Also, watch out for the new key signature (F Major). If you need to, review chord construction here.
And, of course, here is what you just heard being played from the midi file.
Did you notice that the O/C remained constant throughout the selection, even during the tied notes? Often, because they do not know what to do with the extra time (beats), pianists will simply stop playing altogether, waiting for the singers to come back in for the next phrase. This produces an uncertainty in the music, causing the singers to feel insecure and sing softer. If, however, the accompanist plays with a steady beat, then there will be no confusion as to when to resume singing, the singers will sing with more confidence, and the song service will be that much better.
On a side note, remember that, if you click on the music, you can print out these samples and take them to your piano.