In Great Expectations, what secret does Herbert realize at the end of Chapter 41?
After the mysterious appearance of his old convict on the stairs of his lodging at Barnard's Inn, Pip is completely alarmed and repulsed by the news that it is he, Magwitch, who has been his benefactor for his "great expectations" of becoming a gentleman. Then, one night Pip is startled out of his sleep by the arrival of Herbert because Provis has staggered up and opened his jack-knife in anticipation of an enemy. Pip, however, allays the old convict's fears by telling him that it is Herbert.
In vain should I attempt to describe the astonishment and disquiet of Herbert, when he and I and Provis sat down before the fire, and I recounted the whole of the secret.
Thus begins Chapter XLI in which Provis has made Herbert swear on a bible not to reveal any of what is told him. Provis then relates his history: He is the convict whom Pip encountered on the marshes as a child. Having always remembered the kindness shown to him by the boy, Provis has used the fortune that he has amassed in New South Wales working on a sheep farm in order to provide for Pip's becoming a gentleman, apparently as a revenge against Compeyson and a compensation for all his misery in his own youth.
After hearing this secret, Herbert reflects in his face all the repugnance towards the man that Pip himself has felt. Nonetheless, as a true gentleman, Herbert remains polite. But, finally, when Provis departs, Herbert consoles Pip and they confer with one another about what to do with Provis. Wisely, Herbert suggests that Pip get Provis out of England since he wishes to buy Pip various kinds of extravagances which will draw attention to them all. To Herbert's credit, also, he remains Pip's loyal friend and even understands the situation with Provis:
And you have, and are bound to have, that tenderness for the life he has risked on your account, that you must save him, if possible, from throwing it away. Then you must get him out of England before you stir a finger to extricate yourself. That done, extricate yourself, in Heaven's name, and we'll see it out together, dear old boy.
These words exemplify the meaning of a true gentleman; that is, one who is gentle in his heart, not simply one with an aristocratic name and wealth, as all of Herbert's relatives but his father believe.