We were all trussed up in stinger suits (underwater body bags that cover virtually all skin) to protect us from box jellyfish. You don’t want to meet a box jellyfish.

This minuscule but pathologically aggressive little critter, otherwise known as Chironex fleckeri, is rather well-endowed, with no less than eight gonads and 24 eyes. Their stings produce agonising pain and are believed to kill around 100 people a year. And this wasn’t the only danger lurking below.

There were also sharks. The dive master, thoroughly enjoying himself, said that in this stretch of ocean, they were to be expected. Suddenly the music from Jaws began playing in my head and I imagined a gang of great whites waiting just beneath the surface, all saying grace and giving thanks for the food: me.

I had been feeling adventurous. Out hiking the day before, we had parachuted off a cliff, strapped to grinning college students, and landed in a school playground during the mid-morning break. On safari we had heard about spiders as big as medium-sized pizzas. And then there were the cassowaries – ostriches with serious attitude problems – which have been  known to unhelpfully disembowel humans. Call me sentimental, but I like my bowels, and I don’t want to donate them to a bad-tempered bird.

I had signed up for the dive, but bobbing around on the surface, waiting for the signal to descend, my mind was screaming. I very much wanted to cancel this mad expedition. The thought of staring into the cold, black eyes of a shark or the multitudinous eyes of a toxic jellyfish just didn’t appeal.

I didn’t signal my change of mind or climb back into the boat. I dived. There were sharks, but thankfully they weren’t in the mood for a snack.

No jellyfish wafted our way, but I learned a stinging truth about myself in that moment; one I’m embarrassed to admit.

I had submerged only because I was anxious about what my fellow divers would think of me. That anxiety outweighed my concern about aquatic predators. I went through with it for one reason only: I was entirely driven by the potential opinions of strangers.

Fear of other people’s opinions robs us. We don’t bop around at that wedding reception, worried that our clumsy moves might raise a silent titter with our strictly non-Strictly strutting. In discussions, we back away from saying what we think, worried that we might seem foolish, divisive, opinionated or all of the above. Leaders obsessed with what others think refuse to make difficult, potentially unpopular decisions, terrified that some will like them less because of the stand they have taken.

Neurotic anxiety about the verdicts of others is irrational. Most of the time we won’t ever know what they think because they won’t tell us.

It may surprise us to know that the minds of others are elsewhere and not focused on us at all. As Christian writer Ethel Barrett said: ‘We would worry less about what others think of us if we realised how seldom they do.’

And if they do disapprove, and they’re wrong in their judgement, we just need to ignore them. Faced with a mounting clamour of criticism from the Pharisees and their pals, Jesus modelled a calm indifference to their snide asides, and quite literally kept calm and carried on.

So when we’re tempted to be paralysed by fear about what people think, let’s think again and live out loud anyway.