Matthew Poole and continuators on Genesis 19:31

31 And the first-born said unto the younger, Our father is old, and there is not a man in the earth to come in unto us after the manner of all the Earth .

Either 1. In the whole Earth: For they thought the same deluge of Fire which destroyed the four Cities had by this time extended it self to Zoar, and all other places, knowing that the whole World did lye in wickedness, and having possibly heard from their Father, that the World as it was once destroyed by Water, so it should afterwards be consumed by Fire, which they might think was now executed, and that God had secured Abraham from it by taking him to himself. Or 2. In that Land, as the word may be rendred. And her meaning might not be this, that there was no man at all, but not a man with whom they might or durst Marry: For though they knew they left many Men in Zoar, yet the sad experience of the dreadful ruine wherein their Brethren in law were involved made them abhor the thoughts of any Conjunction with them.

(i. e.) Of all the Inhabitants of the Earth. Compare Gen. 18. 11▪