Oscar Pistorius has said Reeva Steenkamp would not want him to go back to prison for her murder, in his first television interview since he fatally shot the model three years ago.
The former Paralympian faces 15 years in prison after his manslaughter conviction was upgraded on appeal to murder.
South Africa's Supreme Court of Appeal ruled last December that the athlete acted "recklessly" by shooting at a locked lavatory door, even if he believed an intruder was inside rather than his girlfriend.
Speaking ahead of his sentencing on July 6, Pistorius - who served 12 months of a five-year prison sentence for manslaughter and is currently under house arrest - said he believed he could better repay his debt to society outside prison.
"I don't want to go back to jail; I don't want to have to waste my life sitting there," he said. "If I was afforded the opportunity of redemption I would like to help the less fortunate like I had in my past.
"I would like to believe that if Reeva could look down upon me that she would want me to live that life."
The athlete said he would not argue with those who believe "they should lock me up and throw the key away".
But he added that many people believe he intentionally killed Steenkamp, which was not proven in his trial or the appeals court.
"Reeva was a fantastic person, but if their premise is based on the fact that I took her life intentionally, which has not been found then it's a very sad thing," he said.