DETROIT – The imprisoned 66-year-old son of a Detroit preacher will soon walk out of a Michigan prison and experience freedom for the first time in more than three decades.

Former Governor Rick Snyder granted a rare commutation in his final days of office, after several law enforcement agencies came forward saying the inmate provided invaluble information exposing corruption in the prison system.

ORIGINAL STORY: Detroit man repents by exposing corruption from inside jail, police say

His identity is being concealed for his own protection. The man has been stabbed and beaten behind bars for helping police and the FBI bust dozens of corrupt prison officials, solve murders and more -- even after being critically injured and nearly dying.

He said he believes God wants him to help to repent for the sins that put him behind bars 30 years ago. Law enforcement officials pushed for his freedom in 2018.

"He spent decades doing whatever he could behind bars to try to help people inside the prison and outside the prison," said attorney Nakisha Chaney.

The FBI and DEA both wrote letters to the very prosecuting attorney who put him away and said he should be freed because he risked his life repeatedly to help law enforcement.

"This guy deserved to get out," said attorney John Smietanka. "He has more than paid his debt to society."

The pleas from law enforcement worked, and Snyder granted clemency, shortening his maximum 200-year sentence to the time he already served.

"I got so emotional," the inmate said. "I just broke down and cried."

He said he didn't help authorities to get out early, but he and those who fought for his freedom are estatic.

"It's a marvel that he's stayed alive as long as he has, and I'm happy that he is going to get a chance to get out and do something else with his life other than get stabbed and beaten," Smietanka said.

The inmate said he cannot wait to get home and see his father, his siblings and the rest of his family.

He said he was a troubled teenager who went down a dark path and that he found God in prison and devoted his life to making a difference.

He is expected to be released from prison before the end of March, but he's not stopping his work and plans to continue to make the prison system safer for inmates and employees.

You can watch Kevin Deitz's story above.