The old man who guards the shore of Purgatory is a solitary figure with a long white beard, his face lit by the four stars that only the first men saw. The text gives him no name: it says he left life at Utica and that he has a wife, Marcia. The commentators' tradition identifies him with Cato of Utica, the pagan who is said to have killed himself rather than surrender to Caesar; it is the tradition, and not the verse, that fixes the name.
In canto I he asks who has escaped the eternal prison. Virgil replies that a lady from heaven sent them and that Dante seeks liberty, "as he knows who for her refuses life". He then appeals to tenderness, by the name of Marcia, and the old man separates the two requests: Marcia pleased him in life and no longer moves him, but the name of the lady from heaven is enough. He orders Dante girded with a smooth reed and his face washed, and disappears.
In canto II he returns as the voice that breaks up the festival. Dante had asked Casella for the love song that soothed his pains, and everyone listened to it without seeing anything else, until the old man shouts: "What is this, slow spirits?" He does not clear a path, he gives direction and motive: run to the mountain and shed the crust that keeps you from seeing God. The souls flee like frightened pigeons in a pasture.
The poem leaves open why a pagan guards the gate of a mountain of salvation. What it shows is an authority that yields to the order of heaven, not to tenderness, and a first lesson: to purge oneself is to shed what keeps one from seeing God, and that begins with haste.