We've already examined (see June 27, 2013, and following days) a sample of Tasso's way of translating the Bible, a Psalm in that case. Here the Scripture being translated and reinterpreted is a well-known hymn from the book of prophet Isaiah, ch. 60. But the very context in which Tasso inserts these lines modifies their meaning. In fact, Isaiah 60 has traditionally been used by Christian authors as a prophecy of the birth of Jesus, together with the Magi / wise men coming to worship Him from the Far East. Here, however, the land to be 'freed' from 'darkness' is Jerusalem, by the hand of the Crusaders; not by chance is the rising Sun the emblem of the main hero in the poem, the knight Richard.
Tomorrow we'll see another, even more intriguing 'updating' made by Tasso on this Biblical text.