“Drawing his finger along the ground, the good Sordello said: ‘Look, e’en beyond this line, the Sun gone, pass nor thou nor any could’.”
. . . . .
Virgil identifies himself to Sordello, explaining that he has been barred from Heaven for his lack of Christian faith. Virgil explains that Limbo, though “melancholy,” is not as grievous and painful as the rest of Hell. Then Virgil asks Sordello how to reach Purgatory proper. Sordello explains that there’s no fixed path and adds that no one is permitted to climb overnight—it’s a law of Mount Purgatory. These figures are in Purgatory because, during life, they were too preoccupied with worldly matters to attend to their souls.