Beatrice is the woman whom Purgatory promises from canto VI and delivers in canto XXX: she appears in the Earthly Paradise, in a cloud of flowers, and, instead of consoling Dante, she calls him by name and accuses him. The biographical tradition identifies her with Beatrice Portinari, the Florentine whom Dante is said to have known as a child; within the poem she is never given a surname.
Before she appears, she is announced. Virgil names her for the first time when he reaches the limit of what his reason can reach, in canto VI, and promises her "laughing and happy" at the top of the mountain. In canto XV he says she will take away every hunger that reason does not satisfy, in canto XVIII he hands her free will, which she understands as a noble virtue, and in canto XXVII it is her name, and no argument, that makes Dante enter the wall of fire.
When she arrives, the scene has three movements: recognizing, judging and ordering him to write. Dante recognizes her before his eyes do, by a hidden power that goes out from her. She says his name, the only time the poem does so, and accuses him with the gesture of an admiral who goes to the stern and to the prow to rouse the men of the other ships. When Dante confesses and is washed, she tells him to look at the chariot and, once back in the world, to write what he saw.
In the common reading, she represents revelation, the theology that takes the place of Virgil's reason. The text gives her character: a demanding woman, who does not welcome but commands, and whose accusation the poem does not soften.