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Pip's benefactor arrives as a mysterious stranger on the steps of his lodging, Barnard's Inn, at eleven o'clock one evening. This event, Pip remarks ironically, "had begun to be prepared for before I knew that the world held Estella." For, the benefactor is not Miss Havisham as Pip has believe, but is, in fact, the man in coarse grey of the marshes who has made his way from New South Wales where he has worked and amassed a fortune from the gift of his former employer. At this recognition of the old convict, Pip is repulsed; moreover, when he learns that Magwitch has been sending the money for him instead of the aristocratic Miss Havisham, Pip is mortified.
However, after his dismay and disappointment, Pip, who yet retains his innate kindness, cannot turn the old convict away who has sustained him. So, he tells Magwitch that he can spend the night in Herbert's empty room. The next day, as Pip feeds Magwitch, he asks the old convict how long he plans to remain in London; Magwitch replies that he has "come for good." Taken aback by this response, Pip worries that there is anywhere that Magwitch can be safe, but the old man tells Pip he can buy a disguising wig and spectacles and "what not." So, Pip tries to secure him some quiet lodging on Essex Street under the name of Mr. Provis as an uncle to Pip.
After finding lodging, Pip goes to Little Britain where he confronts Mr. Jaggers about the truth of who is his benefactor. Mr. Jaggers confirms that Magwitch is such a person; furthermore, after Pip tells him that he always supposed it has been Miss Havisham, Jaggers tells Pip,
"Not a particle of evidence, Pip,....Take nothing on its looks; take everything on evidence. There's no better rule."
Thus, this incident clearly underscores the theme of Appearance vs. Reality which has threaded through Charles Dickens's Great Expectations