When Nashville SC open GEODIS Park with their first home match of the season against the Philadelphia Union on Sunday (4 pm ET | ESPN, ESPN Deportes), you can be sure that the club's popular unofficial mascot will be in the heat of the festivities.

Stephen Mason is the guitarist for Nashville-based Christian rock band Jars of Clay, a title he's held since the early 1990s. He's also a die-hard Nashville SC fan that's assumed an alter-ego as Soccer Moses, and can be seen among the supporters at Nashville's home games sporting the full get-up, including a staff and long beard.

Soccer Moses has become such a popular staple at Nashville home games that co-hosts Susannah Collins and Jillian Sakovits decided to have the man himself on The Call Up to explain his origin story ahead of his upcoming GEODIS Park debut. To hear Mason tell it, the idea was born with inspiration from his friend JT Daly of the indie rock band Paper Route, who yelled "Let my people goal" after watching Nigeria winger Victor Moses score a goal in a World Cup match.

"[Daly] told me that story and I was like, that should be a shirt," Mason explained. "And I was talking to Stephen Robinson, president of The Roadies supporters' group and I was like, 'What if I came as the shirt?'"

Soccer Moses - Nashville SC - February 29, 2020

He did just that at Nashville's inaugural MLS home match during their 2020 expansion season, with broadcast cameras picking up Soccer Moses in the crowd and the footage quickly going viral. From there, the legend was born.

"It was a magical night, NFC [Nashville SC] didn't come out with the win, but it was a stadium full of soccer fans from Atlanta and Nashville," Mason said. "Next morning we're at a hot chicken brunch, and we turn and ESPN's on and it leads with that picture of me, and my wife was horrified and delighted that she was right. And I immediately was like, 'Well, looks like this is sticking.' So immediately websites and Instas and honestly in 2020 landed with Covid, it gave us kind of something to invest in and bring some joy in the midst of all the tough stuff."

Mason didn't necessarily have grand plans for it when Soccer Moses first came to be, but given the response from the Nashville fan community, he's felt compelled to carry on the tradition at GEODIS Park, Nashville's new state-of-the-art, $335 million home with a capacity of 30,000 fans.

"It is like 10 out of 10 on the joy scale," he said. "Everything from writing copy on Instagram posts or just seeing, like last season there was a kid, must have been 8-9 years old turned up in a Moses costume, it was baby Moses. It's kind of one of those things where it just caught and people just started experiencing joy."

For more from Soccer Moses, be sure to check out the latest edition of The Call Up on Tuesday.