This piece was written by Charles Gounod as a melody for J.S. Bach's piano prelude in C major. The words are from a mass celebrating the moment when the angel proclaimed to Mary that she would bear a child who would teach the world how to no longer "miss the mark".
Benjamin Sun (an erhu master from Hawaii) has recorded a beautiful version in the key of D. I've included an mp3 file: [[%ATTACHURL%/bwv846.mp3][bwv846.mp3]] that is extracted from a midi file of harpsichord playing by John Sankey. I've transposed it from the original key of C into G for the Erhu. The mp3 has no melody, it is just the original harpsichord piece by Bach. It makes a nice backup for practicing and for "karaoke" performance.
Treat the bowing patterns with some skepticism. I don't always play it the way I've notated it. Over time it has evolved a bit, and I'm sure you can find some better ways to play it yourself. The main change I've made to this version is that I try to play the octave leaps (like from 6 to 6,) in measure 5 with one bow.