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While on the boat, Dante leans down towards the river and asks one of the mud-encrusted sinners: "Who are you, who have become so ugly?" Seriously.

# When the sinner gives an ambiguous answer, Dante becomes infuriated and curses him. Which is…well…different from his usual responses to sinners, like crying or fainting.

# When the sinner reaches out towards the boat (presumably in a gesture of longing), Virgil pushes him back into the river.

# Then in another switch of personality, Virgil joyously hugs and kisses Dante.

# Why? Dante is making Virgil proud by feeling righteously indignant enough to not sympathize with sinners and instead to rage at them.

# He continues, using his prophesying skills to predict that before reaching the far shore, Dante will see a sight that justifies his insult to the sinner.

# A bunch of muddy sinners attack the same guy Dante did, crying, "At Filippo Argenti!" At which point Filippo goes crazy and starts biting himself.

# Having filled his meanness quota for the day, Virgil turns into Mr. Explain-Everything again, telling Dante they are approaching the city of Dis.

# Dante catches sight of it on the horizon and is struck by how red everything is.

# Yes, red. Apparently, this comes from the eternal flame that burns within the city, signaling that it is within lower (worse) Hell. So says Virgil. In other words, you ain’t seen nothin’ yet.

# When they arrive at the gates of the city, they find a thousand enraged sinners trying to bar Dante from getting through. Because of his alive-ness.

# To recap, we’ve got a thousand angry sinners waving their pitchforks around and spitting at Dante. So Virgil "makes a sign" to fend them off and has a private chat with them.

# Dante can’t hear what they’re saying. Probably because he’s freaked out by the mad sinners and wants to go home.

# The citizens of Dis agree to open their gates, but only for Virgil. The live guy has to go back.

# Dante freaks out at the thought of having to go back on his own, so much so that he tells the reader directly about his fears.

# Then he begs Virgil to come back with him if these sinners are so intent on blocking their way.

# Virgil, his ego puffed up now, scoffs at Dante’s words and says he’ll take care of it.

# So while he does the fast talking, Dante wrings his hands with indecision.

From Shmoop Lit on Dante's Inferno