INDIANAPOLIS — We parked on West 16th Street and walked the final half-mile to the Indianapolis Motor Speedway.

In the company of some 400,000 people, we found our seats. Race cars sat in rows of three on the track, as quiet as worshippers waiting for permission to sing.

The pre-race ceremonies were a moving display of patriotism and respect for armed forces guarding this free land, capped by a state song told, ironically, from the standpoint of someone who has left home and yearns to be “Back Home Again in Indiana.”

Then came “the rush.” Not exactly a “violent wind,” as the Bible describes on the day of Pentecost, but every bit as loud, as 33 Honda 3.5-liter V-8 engines roared to life. People shouted for joy. Racing was about to begin.

Little by little, the sound intensified as slow-speed (just over 100 mph) parade laps gave way to the most exciting moment in sports, when the Chevy Camaro pace car pulled off, the starter flagged green, and cars accelerated suddenly to 220 mph and swooped into the first turn.

Noise filled every corner of the 100-year-old track. Fans were lifted higher and higher by the sound. It was the roar of young dreams, the roar of the internal combustion power that has largely defined the modern age, the roar of drivers being allowed to go as fast as their skills and technology could take them.

The roar of the lead cars coming off the fourth turn and down the straightaway drew us to our feet. Fans let out a mighty roar of their own.

As Jesus’ disciples found on Pentecost, the rush of such a mighty sound can fill the house and transform human lives. I don’t want to compare the Indy 500 with the work of God’s Spirit, but I do note the transformative impact that such a moment can have.

It certainly changed everything for the disciples. They went from hiding to proclaiming; from fear of the religious establishment to confronting the establishment; from settled lives to self-sacrificial lives; from me-first to others-first.

Church leaders like to call Pentecost the “birthday of the Church.” Better, I think, to name it the birth of freedom and courage. For it was on this day that the commandment Jesus gave — “Don’t be afraid” — took root in their lives.

I yearn for the day when Christians will stop being afraid — afraid of offending, afraid of change, afraid of failure, afraid of going broke, afraid of each other. I yearn for the day when the sheer noise of God’s Spirit lifts our spirits and we shout for joy.

Some say we’re in a “post-Christian” era and herald (or bemoan) the victory of “secularism.” I don’t see it that way at all. More accurately, this is a post-courage era, when congregations are paralyzed by their fears.

We don’t need “better religion.” We need “better backbone.” Let’s go down in flames, rather than slink off with our narrow opinions and bank accounts intact.

We don’t need to cleanse our ranks of all divergent opinions; we need to speak boldly, with every voice of our diverse chorus, that God is so thoroughly sovereign and loving that God can welcome us — all of us! — into the household of faith.

(Tom Ehrich is a writer, church consultant and Episcopal priest based in New York. He is the author of “Just Wondering, Jesus,” and the founder of the Church Wellness Project, http://www.churchwellness.com. His Web site is http://www.morningwalkmedia.com.)