Yesterday was the Feast of St. Bernard of Clairvaux. The hymn in question, likely written in the 13th century (or earlier), is an acrostic: the first letters of each stanza spelling out the name BERNARDVS. The meter is the iambic dimeter, that of the original hymns of St Ambrose and other early Christian poets.
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A medieval hymn of St. Bernard
Gregory DiPippo, New Liturgical Movement
Monday, August 21, 2023