Commentary Purg XXVIII 142-144

Ovid's description of the classical 'Eden' (Metam. I.89-11) is remembered closely in this tercet.  One of its particulars is arresting.  Where Dante makes his springtime eternal, in Ovid (Metam. I.107) it became ephemeral and now leaves us every year: 'ver erat aeternum' (the spring was everlasting).  The drama of the Fall and Resurrection is reflected in this tercet.  In this garden humankind was created innocent and fell; nonetheless, the garden awaits our redemption in its eternal unfallen condition, filled with the nectar and ambrosia of the classical Golden Age in its Edenic form: fruit and water (see [Purg XXII 148-150]).

      Singleton (Sing.1958.1), pp. 192-99, points out that the virgin Astraea, or Justice, is a significant presence in both Ovid's and Virgil's presentations of the Golden Age, the last goddess to leave the earth in Ovid's myth, only to return in Virgil's prophecy.  And just so, for Singleton, does Matelda serve in the role of Astraea here in Dante's garden, representing original justice (as well as our memory of the unfallen Eve).