On this last cornice, the seventh cornice, they encounter the lustful. They sing while moving through sheets of fire. They are guarded by the angel of Chastity.
Dante realizes the angel of Chastity took away his last 'pecato' from his forehead and that each angel on every cornice took one away. That symbolizes Dante getting rid of his sins. He is now free of sin.
Don't worry, that was just an earthquake!
Live in MODERATION
Dante and Virgil finally reach the Wall of Fire, it is the last step of purification to enter the Earthly Paradise. At first, Dante is hesitant, but then he agrees to go through to find Beatrice.
On the fourth cornice, they encounter those who committed the sin of sloth; they are punished by being forced to run around without stopping. They are guarded by the angel of Zeal.
In the fifth cornice, they encounter the avaricious and prodigious who are bound by hands and feet and forced to lay with their faces in the dust. They are guarded by the angel of Moderation. Here, they also meet Statius who tells them the occasional earthquakes meant another soul had reached the Earthly Paradise.
On the sixth cornice, they encounter the gluttonous who are forced to stare at delicious fruit but are prohibited from eating it. They are protected by the angel of Abstinence.