Shaq Pays Off Man's Engagement Ring Debt In Generous Act Caught On Video

Just call him the Big Good Samaritan now ...

Shaq paid off some young guy's engagement ring debt at a jewelry store in Georgia this week -- and the amazing gesture was all caught on video.

The Big Diesel explained how it all went down on "NBA on TNT" on Tuesday night ... saying he was in a Zales in the Atlanta area on Monday shopping for some earrings when he noticed a man was stressing over a bill.

Shaq says the guy was trying to figure out a way to set up a payment plan for a ring he was purchasing for his girlfriend ... when the NBA legend felt like he just had to step in.

"I seen the guy come in -- he was just so shy," Shaq said. "He was saying, 'Hey, how much do I owe to pay off my ring.'"

"And I was like, 'My man, how much is the ring?' I'm not going to say the amount, but it's not a lot for me."

So, Shaq whipped out his credit card -- and paid for it right on the spot!!

"I was like, 'You know what? Tell your girlfriend I got her,'" Shaq said. "'I'll take care of it.'"

Shaq added, "At first, he didn't want to take it. He was like, 'Man, I can't do that.' I said, 'Don't worry about it. I do it all the time.' I'm just trying to make people smile, that's all."

The two then posed for a photo -- and it was all really freakin' awesome!!

The best part of the story, though? Shaq says he had an even MORE generous act at a furniture store recently, paying off a bill there for a sweet family.

"This lady, she had an autistic daughter," Shaq said. "And she was also looking to pay for some furniture and I just took care of her. So, I'm into making people happy."

"Whenever I leave the house, I just try to do a good deed."