Picture the open ocean. The sun ripples on the surface, light bends into deep blue, and far below, a silver torpedo is on the move. That torpedo is alive — a tuna — and it has a secret: it can never stop.

For most fish, resting is simple. They pull water over their gills by expanding and closing their mouths, a process called buccal pumping. That steady motion keeps oxygen flowing whether they’re darting through a reef or lying still under a rock ledge. But tuna are different. Their gills are built for speed, not idleness. They rely entirely on a system called obligate ram ventilation. To breathe, they must push forward, water streaming over their gills with every stroke. If they stop moving, the water stops too, and oxygen runs out. Stillness would be suffocation.

They’re not alone in this ceaseless race. Many sharks are designed the same way. Great whites, makos, hammerheads, and even the filter-feeding whale shark all depend on constant swimming to keep oxygen flowing. Bonito, swordfish, and other billfish fall into the same group. The faster the lifestyle, the stricter the rule: motion equals life.

That means for a tuna, the entire ocean is a treadmill. Their survival depends not on resting places but on continuous movement. Day or night, awake or weary, they are always propelling themselves forward through salt and current.

Compare that to marine mammals — dolphins and whales. They too face a challenge: needing oxygen from the air while living in water. But Jehovah equipped them with a different solution. They practice something called unihemispheric slow-wave sleep. Half of their brain rests while the other half stays alert, awake enough to guide them to the surface to breathe. They can nap and swim at once, alternating sides of the brain like a night watchman passing the torch. That gift means they don’t drown in their sleep.

But tuna have no such system. No half-sleep, no safe pause. Just endless forward motion. And yet — that is their wonder. Instead of tiring them out, this design gives them the stamina to cross entire oceans. Southern bluefin tuna have been tracked swimming thousands of miles, slicing through cold and warm currents alike. Their bodies, built like streamlined arrows, turn what sounds like a burden into unmatched endurance.

What does this reveal? That Jehovah designs with wisdom, even when the blueprint looks harsh to us. He tailored tuna and sharks to thrive in the “always moving” lane, just as He tailored whales to breathe air with brains that alternate rest. Different creatures, different solutions, one Creator’s brilliance.

And for us? Isn’t there a lesson in this ceaseless motion? Spiritually, life cannot be sustained by stillness. Jehovah’s chariot is always on the move (Ezekiel 1:19–21). His purpose, His Kingdom, His direction for His people — never stagnant, always advancing. So how could His servants afford to stay still? If we coast, if we stop drawing from Jehovah, our oxygen runs out.

Isaiah captures it beautifully: “He gives power to the tired one and full might to those lacking strength. Those hoping in Jehovah will regain power. They will soar on wings like eagles. They will run and not grow weary. They will walk and not tire out” (Isaiah 40:29, 31, NWT).

The tuna’s endless swim is not frantic survival — it is strength in motion. Likewise, when we keep moving in faith, it is not frantic effort but steady endurance. We move forward with prayer, with trust, with daily strokes through the currents of life, and Jehovah makes sure the oxygen of His spirit flows through us.

So next time you see a picture of a tuna or a shark, remember: some of Jehovah’s creatures must never stop moving. And remember the lesson — neither must we.