Restaurant workers around the country are being photographed with huge smiles on their faces - holding up receipts with tips of up to US$10,000.
Each tab is stamped with the handle @tipsforjesus and bears an illegible signature.
The anonymous tipster has left their trail of generosity coast to coast and even in Mexico. A waiter in Phoenix beams looking at his $2,500 tip. And a $111.05 New York restaurant check includes a $1,000 tip and the words "god bless!" scrawled across it.
Photos of the outlandish tips are posted on the Instagram account "Tips for Jesus" that has more than 50,000 followers. The feed comes with the tagline, "Doing the Lord's work, one tip at a time."
The tipster has yet to come forward. Meanwhile, they're keeping everyone guessing.