Less than 200 years ago, few people suspected that we live in a world saturated with microorganisms.
A handful of scientists, led by Louis Pasteur in the 1860s, had begun to discern the connection between tiny creatures and certain human diseases.
But no one could have imagined that the average human body is home to hordes of bacteria, viruses, fungi, and assorted other entities that are invisible to human eyes.
How much of “you” is you? The current scientific guess is that your body is comprised of about 30 trillion human cells. You also walk around with about 30 to 50 trillion bacterial cells. So half of you, from a cellular perspective, is not human. Most of your body’s cells, of course, are immensely larger than your accompanying microbes. So you can at least be comforted that most of you is you.
Something like 40,000 different species of microorganisms are happy to use your body as a mailing address. There are more than 900 varieties inhabiting your nostrils, 800 on the inside of your cheeks, and at least 36,000 lining your gastrointestinal tract. It’s estimated that one billion bacteria are transferred from one mouth to another during passionate kissing.
The average bacterium lives only 20 minutes. That’s less time than it takes to watch a single episode of Family Feud. Bacteria self-replicate 72 times a day. In theory, a solitary bacterium could produce a pile of descendants that outweighs the Earth in less than two days. Thankfully, theory quickly runs into the hard reality of limited resources.
As Bill Bryson observes in his book The Body: A Guide for Occupants: “Make no mistake. This is a planet of microbes. We are here at their pleasure. They don’t need us at all. We’d be dead in a day without them.”
Bryson is referring to the fact that even though the word “bacteria” conjures up images of dirt and slime, the vast majority of these hitchhikers are harmless. They never give us a thought. Bacteria that live in the soil make it possible for us to grow food, and the ones that live in our gut are essential to our digestion.
Then there are the viruses, which have been much in the news in the past 18 months. They are vastly smaller than bacteria and considerably more mysterious.
There are also a lot of them. Until a few years ago no one suspected that viruses could live in seawater. When someone finally went to the trouble of checking things out, it was discovered that a gallon of seawater contains up to 400 billion viral entities.
Dr. Peter Medawar, the Nobel Prize winning biologist, famously described a virus as “a piece of bad news wrapped up in a protein.” But most viruses, like their bacterial counterparts, have no impact on human beings whatsoever. Bryson points out that they don’t eat, breathe, or do much of anything. They have no means of locomotion. And they tend to infect bacterial cells, not human tissue.
COVID-19, of course, is a frightening exception. Which is one reason why anti-microbial soaps flew off the shelves so quickly in 2020.
Several brands offer this reassuring promise: “Kills 99.9% of germs.”
Unfortunately, independent studies have been unable to confirm such claims. It seems that most soaps merely wash microbes off to a new location. But let’s suppose a best-case scenario. Even if just 0.1% of microorganisms remain alive, that’s still a lot of germs. And since they cling to virtually every surface, they’re reliably found in places that don’t always get reliably washed. A widely-circulated 2017 study, for instance, demonstrated that your cell phone is likely to have ten times more bacteria than your toilet seat – a whole new reason to let your next call from “Unknown Contact” go right to voice mail.
Long before people began to obsess about ridding their lives of microorganisms, millions of men and women felt anguish about the cleanliness of their souls. In a dispiriting, broken world, how can we ever wash away – for want of a better term – the spiritual cooties in our lives?
David the king – writing from the depths of despair about his own dreadful behavior – yearned, “Create in me a clean heart, O God, and renew a right spirit within me” (Psalm 51:10).
What we ourselves cannot accomplish, no matter how hard we try, God offers as a gift.
One of the most moving pictures of this reality is found in the Old Testament book of Zechariah. As part of a vision, the prophet sees the high priest Joshua, who served Israel about 500 years before Christ. It’s one of the darkest moments in the nation’s history. Jerusalem is devastated. The temple, which had been burned to the ground by Babylonian invaders almost a century earlier, remains a heap of ruins.
Joshua stands before the angel of the Lord. That’s a good thing. However, “Joshua was dressed in filthy clothes” (Zechariah 3:3).
The word translated “filthy” is soim, the strongest word in the Hebrew language to express something loathsome. Some commentators suggest that his clothes might be covered with excrement. According to the Torah, the high priest had to keep himself as pure as possible in order to represent God to the people and the people to God. How can he ever do that in such a condition?
Help arrives in the next two verses: “The angel said to those who were standing before him, ‘Take off his filthy clothes.’ Then he said to Joshua, ‘See, I have taken away your sin, and I will put fine garments on you.’”
In our present condition, how can we ever stand before a holy God?
He will have to do the cleansing. He will have to supply clean clothes and a clean heart.
And he is able to do so.
Jesus said to his disciples, “You are clean because of the word that I have spoken to you” (John 15:3). That’s his promise to us, too.
The best news in the middle of a pandemic is that we can all experience the single cleansing that we most need.