《太平广记·卷七十七·方士二》
法善还曾领着皇上去月宫游览，从而聆听到天上的音乐，皇上本来通晓音律，便默记天乐曲谱，回来予以传播，于是成为霓裳羽衣曲。
法善又尝引上游于月宫，因聆其天乐，上自晓音律，默记其曲，而归传之，遂为霓裳羽衣曲。
Fa Zen also once led the emperor on a tour of the moon palace, where they listened to heavenly music. The emperor had a good grasp of music, so he memorized the melody and brought it back to the mortal world, where it became known as the Feathered Robe Song.
<s>[INST] Kindly elucidate the central themes in this passage in English: 法善又尝引上游于月宫，因聆其天乐，上自晓音律，默记其曲，而归传之，遂为霓裳羽衣曲。 [/INST] Fa Zen also once led the emperor on a tour of the moon palace, where they listened to heavenly music. The emperor had a good grasp of music, so he memorized the melody and brought it back to the mortal world, where it became known as the Feathered Robe Song.</s>
Kindly elucidate the central themes in this passage in English: 法善又尝引上游于月宫，因聆其天乐，上自晓音律，默记其曲，而归传之，遂为霓裳羽衣曲。
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Fa Zen also once led the emperor on a tour of the moon palace, where they listened to heavenly music. The emperor had a good grasp of music, so he memorized the melody and brought it back to the mortal world, where it became known as the Feathered Robe Song.
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