It began at a Havertown sushi bar, where he confessed his dream to a parishioner.
Then, last November, his adoring congregation celebrated his 10th anniversary as rector of St. David's Episcopal Church in Wayne by surprising him with the chance to realize his dream.
Tonight at Citizens Bank Park, before the Phillies match bats with the Atlanta Braves, the Rev. Frank Allen's dream will come true when he sings the national anthem.
"I couldn't be more thrilled," says Allen. "I'm very patriotic and I'm a baseball nut."
On hand will be more than 1,100 members of his flock, who are "going to be making a joyful noise," predicts Glenn Porter, a St. David's congregant. "When was the last time 1,100 Episcopalians gathered in public? We're not a showy bunch."
When it comes to singing, Allen, 49, is no sandlot amateur. Endowed with a Pavarotti-like chest and diaphragm, he has a powerful baritone that evokes superlatives.
"If you go to St. David's Church on any given Sunday, you know as soon as Frank Allen comes through the doors of the narthex and you know when he leaves," says Mike Mayer, senior warden of the vestry and the church's chief lay officer.
Allen can belt out a hymn, but the measure of his musical talent is more than mere volume. A student of music in college, he has trained with a professional vocal coach and sung solos in operas. He even has experience singing the national anthem in a ballpark. In the mid-'90s, as an assistant in a parish in Roanoke, Va., he sang Uncle Sam's theme before a game of the Salem Avalanche, the single-A affiliate of the Houston Astros.
In February, he sent an audition tape to the Phillies so they would know what to expect.
"An excellent singer," says Chris Long, the team's director of entertainment.
As a rule, the Phillies prefer that groups or choirs sing the anthem because soloists in the past have sometimes choked. Choking will not be a problem for Allen.
He's been practicing at least 15 minutes a day, often while driving along Lancaster Avenue in his black Jeep Liberty with the windows rolled up. To psych him up, or out, parish pranksters have sent him YouTube snippets of anthem singers clutching and making a hash of it.
He is not daunted. "I know what I have to do," he says, though conceding it's not an easy song, especially the "land of the free" high notes.
"It's more than an octave," he says of the anthem. "Eleven notes instead of eight, so it's a bit out of most people's range and comfort zone."
His colleagues are just as confident.
"Trust me, he's not going to choke," says the Rev. Kevin Moroney, an associate rector. "We're used to performing in front of a tough crowd."
Allen seems destined for this moment, just as he was destined to become a priest after an early career in business.
"The family joke is that I was singing songs before I could put a sentence together," he says.
His family belonged to a large Episcopal church in Dallas, and Allen was soon contributing his voice to the choir. At age 10, he had a lead role in Handel's oratorio Athalia. At St. Mark's, a private Episcopal prep school in Dallas, he sang Bach cantatas and in his senior year appeared as a soloist with three professionals.
He won a music scholarship to Duke University, where he majored in history. But he studied music all four years, taking part in opera workshops and recitals.
After college, he came north to work for R.M. Shoemaker, a construction-management firm based in West Conshohocken. He had a knack for sales and spent 11 years there. But it was his church activity - he led the youth group at the Church of the Redeemer in Bryn Mawr - that fulfilled him.
In 1992, he enrolled at Virginia Theological Seminary in Alexandria, and in 1997, he was chosen to lead St. David's.
"I've traded one sales job for another sales job," Allen quips.
With 950 active families and 3,000 members, the parish is thriving. It is the largest of the 149 parishes in the Episcopal Diocese of Pennsylvania, which encompasses Philadelphia, Bucks, Montgomery, Delaware and Chester Counties. St. David's is known for its picturesque country church, erected in 1715, and popular fair, which takes place in October and raises more than $100,000 for the church's outreach programs.
Married to a pediatrician and the father of three boys, Allen is described by his parishioners as a forceful preacher, inspirational leader and effective manager.
"The parish has grown enormously in his time," says the Rev. Sandy McCurdy, an Episcopal priest who assists in the parish. "He's been able to hold this big ship together."
After he rashly confessed his ballpark dream, a cabal of St. David's folk, some wearing collars, conspired to make it happen. Ringleader Glenn Porter pitched a proposition to the team: If we promise to sell at least 300 tickets, may our pastor sing?
It helped that one of the Phils' owners, who prefers anonymity, belongs to St. David's. So, to be candid, a string or two may have been pulled.
At the 10th anniversary dinner in November, when the Phillies singing gig was announced, "an incredible roar went up," according to an informed source. The 400 people at the banquet clapped and hollered in a raucous public display of affection that was most un-Episcopalian.
As for Allen, "he almost fell over," Porter reports. "He got this swoony look, put his hand over his heart and kind of wobbled."
"I teared up," Allen says. "It really touched me."
Ticket sales took off. A church flyer advertised:
Cost of a Phillies ticket: $19
Bus ride to Citizens Bank Park: $22
Hatfield Dollar Dog Night: $1
Frank singing the National Anthem: Priceless
More than 1,100 parishioners are expected to show up, though it's not necessarily a reliable index of Allen's popularity.
"Remember, it's dollar dog night," Moroney says, "and that brings out the worst in Episcopalians."
When his sons were growing up, Allen coached three baseball/T-ball teams - all named the Phillies. He watches or listens to Phillies games all summer long, win or lose, religiously. He admires the team's abiding hustle and work ethic. "They're gamers," he says.
Now that he's on the brink of realizing one fantasy, Allen has concocted another.
"I'm hoping the Phillies not only win, but that they pitch a no-hitter," he says. "And I'm hoping the owners are so impressed that they ask: 'Who was that fat, bald priest who sang the national anthem?'
"I want to be to the Phillies what Kate Smith was to the Flyers. I want to power them to the World Series."