Chinese Zither (or Gu Zheng) performed by Yun Yao
Chinese flute performed by Cai Rongwen
Chinese Erhu performed by Lan Shizhe

A modern poem that describes the theme of the music:

When the Law of the Universe is once again spread in the human realm,
Its cultivators may reside in the secular world during the cultivation practise,
But their minds will become as clear as a mirror and as determined as a boat sailing towards home because they are inspired by the wisdom of the Law of the Universe embedded in them.
They can look back at the past in peace without any emotion.
When they play music on the mountain, it is as though the moon is listening and responding to the music.