The bent souls pray the Lord's Prayer together as they inch along. Dante renders their prayer in full, adapted to the condition of souls in purgatory: they ask God's will to be done on earth — for earthly humans who cannot, as the souls in Purgatory now can, always desire it perfectly. The souls pray for others who cannot pray as they can; the prayer enacts the very communion it describes. It is one of the poem's most formally beautiful passages.
Dante speaks with Oderisi da Gubbio, once the greatest illuminator of manuscripts in Italy. He is candid: in life, his pride in his own work was immense; now he sees it for what it was. He offers Dante a meditation that is simultaneously one of the most honest and one of the most melancholy passages in the Commedia. Cimabue once reigned in painting — now Giotto has eclipsed him. In poetry, Guido Guinizelli held the glory — now Guido Cavalcanti has taken it from him; and perhaps, Oderisi hints with a sidelong glance, someone else will take it from Cavalcanti in turn. (That someone is Dante himself — but Dante's dramatic discretion is notable.) Earthly fame is a wind that blows from every quarter and changes its name. A thousand years is a blink of eternity. What does it matter?
Oderisi then points to another soul bent under a heavier stone than any: Provenzan Salvani of Siena, once the dominant lord of all Tuscany, who humbled himself publicly in the marketplace of Siena (begging on his knees to ransom a friend from Charles of Anjou's captivity) — an act of self-abasement that shortened his time in Ante-Purgatory and allowed him to begin the climb. The lesson: voluntary humility in life is worth more than compulsory humility in death.