In Chapter XLI of Great Expectations, there are a couple of incidences of irony. For one, when Pip declares to Herbert that he can no longer accept money from his benefactor now that he knows what and who he is, Pip states that the only thing that he knows he can do to earn money is to become a soldier. But, Herbert suggests,
"You would be infinitely better at Clariker's house, small as it is. I am working up toward a partnership, as you know."
Pip, then, remarks,
Poor fellow! He little suspected with whose money.
The suggestion of Herbert's is ironic since it has been Pip himself who has procured the position for Herbert with a monetary gift from Miss Havisham. Now, Herbert wants to give Pip a position.
In another instance, as Pip and Herbert both feel aversion towards the old convict, they discuss what plans Pip can make to be free of him. While they consider this dilemma, ironically, the old goodness of Pip emerges in the midst of his antipathy for Provis and he cannot simply allow Provis to "throw away" his life if Pip rejects him. So, they seek a plan that will be safe for Provis.
Finally, when the old convict makes Herbert swear to hold secret what he is about to reveal, he makes Herbert hold a Bible which, ironically, he carries with him. Again, there is the blending of good and evil in this situation as there is in the first example.