how does magwitch's life story affect what you think of him?what effect does it have on pip?

Magwitch's beginnings in life were not unlike Pip's in the sense that he was a poverty-stricken orphan; one key difference, although, was Magwitch's constant skirmishes with the law from the time he was very small. Although Pip's home life with his cruel older sister wasn't exactly ideal, he did have a roof over his head and his kind brother-in-law Joe, who apprenticed him when he got a bit older. Pip and Magwitch's unlikely encounter in the marshes when Magwitch was on the run was a pivotal moment that stayed with the older man forever; he never forgot the little boy, Pip, who, though scared, or perhaps because he was scared, brought the outlaw food when he was running from the police. Magwitch ended up on a sheep ranch in Australia where he vowed to repay the little boy one day by turning him into a "gentlemen" with the money he earned.

Magwitch's character is one of the ways Dickens develops the theme of honor and true character in his novel. Magwitch has made many mistakes, it is true, but his years long struggle for redemption is sincere, and he comes to think of Pip as his own son. In many, maybe most ways, Magwitch is more honorable and decent than many of the people Pip comes into contact with; at the end of Magwitch's life, Pip recognizes that Magwitch is at his core a better person than even he himself had been:

For now, my repugnance to him had all melted away, and in the hunted wounded shackled creature who held my hand in his, I only saw a man who had meant to be my benefactor, and who had felt affectionately, gratefully, and generously, towards me with great constancy through a series of years. I only saw in him a much better man than I had been to Joe.