Although reserved to the bishop, this blessing may be conferred by a priest who secures the faculty. The blessing of Epiphany water is of Oriental inspiration. The Eastern Church has long emphasized in its celebration of Epiphany the mystery of our Lord's baptism in the Jordan, and by analogy our baptism. Albeit the mind of the Western Church has not neglected this aspect, as the texts of the feast demonstrate, in practice Western Catholics have concentrated on the mystery of the Magi. The Latin Rite has adopted this blessing of the Orient, and officially included it in the Roman Ritual on December 6, 1890. But for many years previous, diocesan rituals, notably in Germany, had contained a blessing of Epiphany water.)
This is taken from the 1964 version of the Roman Ritual translated by Philip Weller.
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