John Gill Commentary Genesis 19:6

"And Lot went out unto them to the door, and shut the door after him." — Genesis 19:6 (ASV)

And Lot went out at the door unto them
At the door of his house:

and shut the door after him ;
the door of the passage to his house, the courtyard door, for another word is here used; unless the one was properly the door, and the other a hatch: however, this precaution of shutting it was used to prevent the men of Sodom rushing in, and taking away the men by violence; and that Lot might have some opportunity of trying what he could do by arguments, to prevail upon them to desist from their attempt.