Quote 43
I turned my head aside, for, with a rush and a sweep, like the old marsh winds coming up from the sea, a feeling like that which had subdued me on the morning when I left the forge, when the mists were solemnly rising, and when I laid my hand upon the village finger-post, smote upon my heart again. There was silence between us for a little while. (30.41)
Just in case we're not getting it, Dickens basically lays it out for us here: the mists of Pip's hometown are an external representation of the mists inside his head. External is internal; internal is external.
Quote 44
Many a time of an evening, when I sat alone looking at the fire, I thought, after all, there was no fire like the forge fire and the kitchen fire at home. (34.1)
It's not all marshes and darkness down by the river: Joe's forge is cozy and warm, especially once the threat of Mrs. Joe is neutralized. This just might be the most home-like of any place Pip goes.
Quote 45
As I declined the proposal on the plea of an appointment, he was so good as to take me into a yard and show me where the gallows was kept, and also where people were publicly whipped, and then he showed me the Debtors' Door, out of which culprits came to be hanged: heightening the interest of that dreadful portal by giving me to understand that "four on 'em" would come out at that door the day after to-morrow at eight in the morning, to be killed in a row. This was horrible, and gave me a sickening idea of London: the more so as the Lord Chief Justice's proprietor wore (from his hat down to his boots and up again to his pocket-handkerchief inclusive) mildewed clothes, which had evidently not belonged to him originally, and which, I took it into my head, he had bought cheap of the executioner. Under these circumstances I thought myself well rid of him for a shilling. (20.19)
Pip's (and our) first introduction to London life appropriately (or inappropriately) involves a tour of the yard where criminals are publicly tortured or executed. Fun, fun, fun. But these aren't necessarily horrible, heinous, bloody crimes that would induce such public punishment (in our 21st century minds)—we hear about the "Debtors' Door" suggesting that people are often punished for issues of money and debt (not exactly the bloodiest crimes ever). There's close relationship between crime, money, and survival.