Mike McDonnell was a 10-year-old altar boy when he says a priest first molested him.

Now 49, he is one of more than 1,000 victims of an estimated 300 "predator priests" in Pennsylvania, figures revealed by a state grand jury earlier this month.

Following the grand jury report, McDonnell has revealed a motive for his 2011 conviction for stealing $100,000 from the Catholic church: Revenge.

The Philadelphia resident, who is the local leader of Survivors Network of those Abused by Priests (SNAP), said the theft, as well as his struggle with alcoholism, are connected to years of sexual abuse.

"Things would manifest themselves and I would be forced to let it out and look at that fear, anger and resentment," he told NBC News in an interview.

As a recovering alcoholic — he now works as a counselor at a drug and alcohol treatment program — McDonnell says it's his duty to come clean. "For me it's important to be honest and share that story," he said.

"I didn't run from this issue."

The Archdiocese of Philadelphia later paid for counseling sessions for McDonnell, and one of his alleged abusers was defrocked. But McDonnell said he still needed to steal. The abuse, he said, "provides the backdrop for what happened."

The issue for him now, following the release of the grand jury findings, is that the church hasn't faced its own consequences, he said. McDonnell says he served nearly a year's worth of "work release" monitoring on the job for his theft.

"I was held accountable," he said. "Why shouldn't they be held accountable."

McDonnell wants Pennsylvania to eliminate any statute of limitations for child sex crimes cases.

"I’m proud to stand with survivors and victims to seek justice and expose predators," he said.