A letter arrived. It read: "Five-and-a-half years ago I did something terrible to you..."

About five and a half years ago, a person with a drug addiction stole someone’s wallet, pocketing their cash and throwing the discarded wallet into a nearby bin.

Now sober, the former addict has returned the money and written an apology letter to their victim. A photo of the letter was uploaded to Reddit along with the returned money.

“About five-and-a-half years ago I did something terrible to you,” the letter begins. “I stole your wallet out of your purse.

“I was a drug addict wanting to take money from whoever I could to get my next high.”

The letter writer explains they took the cash out of the wallet, along with the victim’s Best Buy card, and then threw the wallet into a nearby bin.

"Not long after that I went into a treatment facility and got sober," they add.

The anonymous person goes on to explain they recently found the Best Buy card and tracked down where their victim worked, so they could return the money and apologise.

"I can't imagine the frustration and despair I put you through, not to mention all the time and effort looking for it and getting all new stuff," they wrote.

The letter writer admits what they did was "unforgivable", but they wanted to send a "small amount of money" as an apology.

"I will also never hurt someone in that way ever again and will continue to live an honest life," they wrote.

"I wish you nothing but happiness, prosperity and good health."

When the letter was posted on Reddit, other users also shared their own stories of redemption and forgiveness.

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"I had a buddy steal $100 from me and return it a couple years later when he got off heroin," one person commented. "I respected him a lot for that."

"[When I was at work as a teenager] a man tried to steal lunch meat and bread and got caught. The man pleaded with us not to call the police. He said he was just hungry. My boss paid for the lunch meat and bread and added a jar of mayonnaise and a jar of pickles," someone commented.

"My boss told him to pay him back when he got on his feet. About a year later, the man came back and reimbursed my boss. That was almost 40 years ago. I'll never forget it," they added.

"This brings tears to my eyes. I'm an addict in recovery. Five years clean. Seeing the results of someone who is trying to better themselves is one of the greatest feelings I have experienced. Being able to go from a junkie who is stealing from an innocent person to get high, to a responsible, productive member of society who is willing to do whatever it takes to make things right is truly magical," one Redditor shared.

What do you think of the letter writer's apology?