Commentary Purg XIII 85-93

The protagonist's labored and heavily rhetoricized captatio (including periphrastic references to the twin rivers of purgatory, Lethe and Eunoe) is perhaps meant to contrast with Sapia's far more immediate and direct response ([Purg XIII 94-96]).  He wants to find an Italian for his cast of characters and promises, in return, a prayer to speed the process of purgation.  How ironically we are meant to take this speech is not clear, but Bosco/Reggio (DDP Bosco.Purg.XIII.73-93) are derisive about Dante's 'overblown rhetoric' here.