Commentary Par XXXI 28-29

In [Par XXXI 27] the saints are said to aim their gaze at a single target.  Now the poet speaks of that single essence as a 'star,' but also as the Trinity, a 'threefold Light,' bringing joy to all the blessed who behold it (and they all do).  Some of the early commentators are less clear than they might be that this is not an 'invocation' or part of the prayer that Dante will address to God in [Par XXXI 30].  This is an example of apostrophe, one of praise, and not part of a request.