The poet Dante has many things to learn. He has lost the true path and he's lost his way to God. He's in danger of ending up in Hell, so Beatrice intervenes, sending Virgil to guide Dante through Hell and Purgatory. Dante is at times fearful, at times ashamed, at times curious, and at times full of justified anger. He is filled with pity for the poor souls in Hell when he first encounters them, but as he learns, he sees that God's justice is perfect. Readers go along with Dante as he experiences the horrors of Hell and learns important lessons along the way.
Virgil travels from Limbo—the first circle of Hell—at the request of Beatrice, who lives in Heaven. He has traveled through Hell once before, and he is equipped to guide Dante on his journey. In Inferno, Virgil is also symbolic of human reason, so his strengths and weaknesses reflect Dante's view of the benefits and limitations of human reason. At the entrance to Dis, for example, Virgil requires divine help, showing that human reason can only take a person so far.