The narrator laments that compared to the antique world, the modern world is corrupted and lacking in virtue. In fact, right and wrong have flip-flopped, and what was once called wrong is now called right. One of the old virtues was justice, and so the narrator offers up a poem in praise of Arthegall, who was an instrument of justice in the world.
The narrator’s longing for the past makes sense, given that the whole poem is written in an archaic language and deals with events set in the past. This might seem to contradict the poem’s stated goal of praising Queen Elizabeth (the present ruler), but the poem often finds ways of connecting her rule to a supposedly more virtuous past.