He is an old man now — a husband, father, and beloved figure in a storied church in the heart of Boston — but in his mind’s eye he can still see the little boy who woke up on that wonderful Christmas morning a long time ago to what seemed like nothing less than a miracle.

Little Bob Yearwood had asked Santa Claus for a bicycle. His mother warned him not to get his hopes up. But 70 Christmas mornings ago, the little boy found a beautiful blue Schwinn under the family Christmas tree. A cherished moment he’s never forgotten.

“I loved that bike,’’ Yearwood, 81, told me the other morning at Trinity Church, where he has been a fixture now for nearly a half-century. “I had it for a long time. I rode that bike on Christmas all day long. Your mom — Santa — went and got you a bike. Others didn’t get that. So you’ve got to be really thankful.’’

Ask around Trinity Church — Henry Hobson Richardson’s sandstone-and-granite masterpiece — and you’ll discover that Bob Yearwood is something of a gift himself, a tall, soft-spoken man who’s known as the unofficial mayor of Copley Square.

His real title is church verger, an office that dates to the earliest days of the Church of England. Vergers were responsible for preparing for church liturgies and taking care of church buildings.

Bob Yearwood does all of that. But the job description does not capture the full essence of the man, who will carry gold candy coins in his pocket to hand out to children when he portrays one of the kings as he always does at the Epiphany in early January.

“He’s the glue who holds it all together,’’ said Sandra Marxen, a church volunteer archivist. “You’ll see little kids, tiny kids, hanging on the end of the pew waiting for Bob because he’ll fist bump them when he goes by.’’

The Rev. Morgan Allen, a Louisiana native who was formally installed as Trinity Church’s rector in September, said he first met Yearwood at his post behind the church’s front desk.

“Bob is at the intersection of the square outside and the congregation inside,’’ Allen said. “Anyone who has a tenure as long as Bob’s carries two virtues: constancy and loyalty, both of which are of a very high value and high importance to me and to this parish. Bob carries them so generously.’’

Bob Yearwood was born in the summer of 1938, the older of two children. His father, who died of tuberculosis when Yearwood was a young child, worked as a railroad porter. His mother, a housekeeper, served dinners to college professors in Cambridge.

He graduated from Boston Trade High School for Boys and went to work installing car windshields on the assembly line at General Motors in Framingham, later working at the General Dynamics shipyard in Quincy.

Eventually he went to work for a construction company that had done work for Trinity Church. And then the church rector hired him as a sexton, or maintenance man. It was a job that would change his life.

“A sexton is a person who has many duties in the church,’’ he said. “He makes sure everything gets done. Things get set up. Sort of like a facilities guy.’’

When his job description changed to verger, he had to look the word up in the dictionary. And he liked what he saw.

“Now you’re part of that clergy staff,’’ he explained. “You’re part of what makes it work. Sort of like the lead man at funerals. At weddings. You make sure it all gets done.’’

He started in 1970. He performed landscaping and minor repairs. He washed floors. He replaced burned-out light bulbs. About that time, he met his wife, Judith, with whom he has three daughters.

“I’m a blessed man,’’ he told me.

On Sunday mornings, Yearwood wears a black cassock and carries the verge, a ceremonial rod topped with a brass ball and a small cross.

“It means the world to me,’’ he said of his church position.

He gets to work at 8 a.m. and leaves most days at 3 p.m. except for Mondays – his late day – when he gets through at 6 p.m.

He’s seen little boys and girls grow into husbands and wives, fathers and mothers. He’s calmed the nerves of jittery brides at weddings.

“It’s all about the people,’’ he told me. “You’ve got to make that connection with the people. The young folks – you’ve got to talk to them. I tell them, ‘Look, whatever you need, you come see me and I’ll take care of it.’ ’’

He stood tall in the sanctuary on Sunday as the offertory hymn echoed through the old, historic church bedecked in Christmas greens, its wreaths adorned with red bows.

“What can I give him, poor as I am?’’ the choir sang. “If I were a shepherd, I would bring a lamb. If I were a wise man. I would do my part. Yet what can I give him. Give my heart.’’

On this Christmas, Bob Yearwood said he will thank God for his family. A 20-year survivor of colon cancer, he will thank God for his health.

“It’ll probably be the greatest Christmas ever because I’m alive,’’ he said. “Put that in your book, OK? I’ve served under seven rectors and I’m still rockin.’ ’’

When I asked Yearwood what his work in the church has taught him about God on this birthday of Jesus, he flashed a broad smile.

“It means it’s all true,’’ he said. “All the people you’ve come in contact with over the years. People have said, ‘Hey, Bob Yearwood is an all right guy.’ So you know it’s God’s will that you continue in this situation.

“This is a great situation to be in. Because, look it, you love the people. But do the people love you? That’s my poem. I love the people. That’s what makes Trinity. Not me. I don’t make Trinity. It’s the people who make it. That’s where I get all this energy from.’’

It was a Christmas card of sorts from the man who makes the trains run on time at Trinity Church.

When I asked Allen what Bob Yearwood means to the church congregation he serves during this Christmas season, he paused for a considerable length of time.

It was a silence that almost grew uncomfortable, but then didn’t because, finally, he said this:

“The Christmas story is a story of humility. The humble setting for Jesus’ birth. The humility of Joseph and Mary to say yes. The humility of God to consent to incarnation, to become one of us.

“And with Bob — setting his 50 years of ministry in the context of the Christmas season — I’m most impressed with his humility. Whereas others might carry such a long and distinguished tenure with entitlement, Bob offers it as a gift, humbly, for me and for our congregation and for our community.’’

With his gentle bearing and in his soft voice, that’s simply Bob Yearwood’s way of saying Merry Christmas everyone.

Thomas Farragher is a Globe columnist. He can be reached at thomas.farragher@globe.com.