Vernacular song in English, c. 1170

While researching for my MA thesis, I have come across a nice passage in Roger of Wendover's chronicle (mid-13th century) quoting a vernacular English song ("canticum illud Anglico idiomate") whose composition Roger ascribes to the early 1170s and mentions in connection with an apparition of the Virgin to St. Godric. He then gives the Latin translation.

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