I ended up in Bronte because the public school taught Spanish — which my children, who were 8 and 6 when we arrived, had mastered in Mexico and at their bilingual school in Brooklyn. In our new home, they had another language to learn. About nature. About a world where the sublime and the scary flow together.

Australia’s anthem describes the country as “girt by sea.” Worldwide, about 40 percent of the population lives within 100 kilometers, about 62 miles, of an ocean; in Australia, 85 percent of the country’s 25 million people live within half that distance. Speedo got its start here in 1914, and even inland — in arid towns the color of dust — public pools are as common as playgrounds. Somehow, swimming just seems to be everywhere, and expected of everyone. In Bronte, most people seem to know someone who has tried to swim the English Channel.

For my son, Balthazar, known as Baz, and his younger sister, Amelia, the integration process began with a junior lifesaving program called Nippers. For generations, it has been a Sunday ritual. Thousands of nippers ages 5 to 14 invade Australia’s beaches from October through March to race on the sand, swim deep into the ocean and practice using rescue boards. The cutesy name doesn’t begin to capture what the action looks like — every age group has its own colored swim cap; every child has his or her name on it and a neon pink rash guard, better known in Australia as a rashie. Parents trained as lifesavers are their guides in the water, wearing orange rashies to further brighten the scene.

The first time I saw it, I was tempted to laugh. It reminded me of Baz Luhrmann, the Australian director of fabulous films like “Strictly Ballroom” and “Moulin Rouge!”

But the longer I stayed, the more I started to think of it as summer camp (or boot camp?) for courage and community. The children pushed one another to finish every task. They confronted the punishing surf together. Fear and tears were simply ignored, not coddled, not denied.

One day, my son found himself at the center of it all. He was riding a board in, bobbing on waves twice his height until he reached the break zone. A wave lifted him up and — with the force of a freight train — crashed him into the shore, tumbling the boy through sand and surf.

I ran to him, trying to calm my racing heart as a gaggle of teenage girls gathered around him first. “Best wave of the day,” one said. Baz could barely breathe, his face was covered in snot, tears and sand. A few minutes later, he was smirking with pride and ready for another go.

My daughter proved to be even braver — she was the one persuading her skittish friends to jump off cliffs or go for long swims or for another ride on the rescue boards.

And then it was my turn. Baz challenged me. Amelia concurred: Dad needed to get his Bronze Medallion, the lifesaving qualification that would earn an orange rashie.

It was time to become proficient.

A Personal Struggle

A lot of people who have been swimming for sport or exercise since they were young write and talk about it with an affection usually reserved for romantic poetry.

My approach favored four-letter words.

In my first attempt to qualify for Bronze Medallion training, I failed. I couldn’t swim 400 meters in less than nine minutes, as required. I finished in 10 minutes 17 seconds, gasping for air.

That led me to take swim lessons in my mid-40s from the same enthusiastic young woman who taught Baz and Amelia when we first arrived in Australia.

Humiliating? Yes. But the worst part of swimming was the actual swimming. At Bronte Baths, the ocean pool carved into the sandstone cliffs at Bronte’s southern edge in the 1880s, every 30-meter lap felt like a climb up Mount Everest.

Eventually, I began to improve. At some stage, I switched up my freestyle technique, breathing every third stroke instead of every two, which helped me glide and see conditions to my left and right — which became more important when I ditched the pool for the ocean. Bondi Beach was where I had learned to surf, so I started swimming there. With no lanes and no one swimming next to me, I started to enjoy practicing and exploring. I marveled at silvery fish and underwater sand patterns. One day, I even wandered into a pod of dolphins darting and diving while I stared in awe for as long as I could hold my breath.

When it was time for me to try the lifesaving test again, after a few months, I finished the 400 meters with more than a minute to spare.

New struggles followed. As part of the training, we were expected to swim together at 6 a.m. It was spring: The water temperature was below 65 degrees. The quest for proficiency also involved group CPR and rescue simulations, which meant chest compressions close enough to smell each other’s breath. We were a bunch of strangers, men and women, around 15 to 50 years old, with different backgrounds, jobs and political views. None of which mattered. We bonded to build our skills. We passed not because we were great but because we were good enough — collectively, even after a wave crashed our swimmer off a yellow spinal board.

Proficiency, I realized, is not like victory, success or whatever else dominates America’s hierarchy of goals. It’s more forgiving, more inclusive, more noble — if we make it a priority. And do we? How often do any of us seek out a risk or a physical and mental challenge unrelated to work or achievement, with an allowance for error, interdependence and grace?

Researching a book about all of this — Australia, risk, community — I discovered the broader benefits of becoming proficient. Martin Seligman, an American psychologist well known for two very different lines of inquiry (learned helplessness and positive psychology), told me that a quest for competence can offset what he called a worrying trend of American fragility. For decades, he said, our culture has sought protection for feelings, believing that self-esteem is the spark for achievement. But that’s backward, he explained. People do not do well because they feel good; they feel good because they do well, often after failing and improving.

Maybe children are the ones to emulate. Here in Sydney, the new Nippers season has just begun. While my son has persuaded me to let him enjoy aquatic life with just water polo and surfing, my daughter continues to gain strength from Australia’s Sunday morning ritual.

Amelia is 11 now, and together we sometimes swim near where I saw that bull ray. Recently, when the surf was uncharacteristically calm, we jumped off the rocks by Bronte Baths and made our way south to where we had never gone because the usual waves would smash us to pulp. We could still feel the strong currents and we knew there might be sharks nearby, so we stayed close together. Neither panicked nor reckless, we swam a few hundred meters without noticing the distance until I saw another wonder of the deep — a blue groper, a giant fish the color of a noon sky that is so slow it is protected from spearfishing.

“Over here,” I yelled. “Blue groper!”

Amelia was next to me in a flash, then down below. I followed right behind, silent and at peace in a foreign realm, pulling myself toward the beautiful fish and the brave little girl.