Raskolnikov states with all certainty that his motive for the crimes:
"was his miserable position, his poverty and helplessness, and his desire to provide for his first steps in life by the help of the three thousand rubies he had reckoned on finding. He had been led to the murder through his shallow and cowardly nature, exasperated moreover by poverty and failure."Dunia, who later marries Razumikhin, keeps in contact with Raskolnikov, and later Sonia after they leave for Siberia, but Dunia and Raz concocted a story about his going away for a long time in order to protect their mother; however, she always knew more than they thought, and soon after, she falls ill and dies.
Raskolnikov suffers bitterly during the beginning of his sentence in Siberia, and the other prisoners do not like him. His greatest struggle is his "wounded pride," which causes his illness.
"If only fate would have sent his repentance...that would have torn his heart and robbed him of sleep...But he did not repent of his crime."Still stuck on his theory:
"In what way was my theory more stupid than others that have swarmed and clashed from the beginning of the world?"He continues:
"Of course, in that case many of the benefactors of mankind who snatched power for themselves instead of inheriting it ought to have been punished at their first steps. But those men succeeded and so they were right, and I didn't, and so I had no right to have taken that step."The only crime he committed, according to his thinking, was that he did not succeed and had confessed it.
In prison, while he was ill, he has a vivid dream about the world condemned to a plague in which all are destroyed except a few chosen ones who are infested with microbes of intelligence and will. It causes men to become mad to the point where they believe they alone have truth. They turn on each other, and no one knows how to judge evil or good.
Sometime after this, he comes to the realization that he loves Sonia, who has remained with him in Siberia. The reader learns that he is beginning his renewal process to become a new man. (Interestingly, it happens around Easter.) Though it seems unlikely since the only Raskolnikov we know is disconnected from people and unable to love, it is almost as if he has snapped out of his delusion and can now live a normal life again. That is, after he finishes the remaining seven years of his sentence.
I guess he has a long time left to renew himself.