This is Jacqli's hymn Sphilia from Ar Tonelico II: Melody of Metafalica. It's used when Jacqli is trying to understand the Heart of Gaea.
Source: http://artonelico.isisview.org/viewtopic.php?f=14&t=133
Translator: Fernia Namanac
I DID NOT TRANSLATE ANY OF THIS SONG AT ALL. PLEASE SEE SOURCE.
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