NEW YORK (CBSNewYork) — An Upper West Side bartender thought a generous tip was too good to be true, but it wasn’t.

Instead, she found out the nationwide “Tips for Jesus” movement had made its way to Manhattan and into her pocket.

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As CBS2’s Andrea Grymes reported, Caitlin Cahill has plenty of reasons to smile these days — about 5,000 reasons to be exact.

Cahill was working at Guyer’s on the Upper West Side last Tuesday when two men came in.

“It was a really slow, quiet night. We were just chatting for a while,” Cahill said.

One of the men was Jack Selby, a former PayPal executive, who sat at the end of the bar with a friend for more than two hours. It was his first time at Guyer’s.

What happened next, apparently, wasn’t a first for him.

“Out of nowhere he mentioned ‘Tips for Jesus,’ and asked if I knew what it was,” Cahill said. “I set yes, and he said, ‘well that’s me.’ I thought he was joking at first.”

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Tips for Jesus are random acts of kindness in the form of huge tips. Many are tracked on an anonymous Instagram page.

The last one was a year ago. Cahill was about to be the next lucky recipient.

“I looked at the receipt and sure enough he left me a $5,000 tip,” she said.

5,000 bucks on a $100 check, with the words “We Back!” scrawled on top.

“I was a little taken aback. I said ‘are you sure?’. Maybe he had a good time, maybe he was feeling generous,” Cahill said.

Whatever the reason, she’s grateful. Her boss says she’s happy for her.

“What a cool thing, this guy Jack,” owner Cindy Guyer said. “I’d like to meet him. I hope he comes back again.”

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Until then, the lucky bartender says she’s heading straight to Bergdorf Goodman.