Washing hands as divine inspiration?

Some Christian apologists argue that there's impossible scientific knowledge in the Bible in the passages that instruct people to clean themselves with fresh water to avoid and clean disease.

This argument is extremely naive and infantile. There's absolutely nothing strange about a culture finding out from experience, and deduction, that dirty water is bad for one's health, while clean water is better. Why would anybody think this shows some kind of impossible knowledge from divine inspiration? It's not even any kind of marvelous feat of knowledge or deduction, but something quite trivial.

However, the argument falls really flat when we examine what Jesus had to say about the subject. In Mark 7 we have this story:

The Pharisees and some of the teachers of the law who had come from Jerusalem gathered around Jesus ² and saw some of his disciples eating food with hands that were defiled, that is, unwashed. ³ (The Pharisees and all the Jews do not eat unless they give their hands a ceremonial washing, holding to the tradition of the elders. ⁴ When they come from the marketplace they do not eat unless they wash. And they observe many other traditions, such as the washing of cups, pitchers and kettles.)
⁵ So the Pharisees and teachers of the law asked Jesus, “Why don’t your disciples live according to the tradition of the elders instead of eating their food with defiled hands?”

What a wonderful opportunity for Jesus, the son of God, to demonstrate supernatural divinely inspired knowledge about microbes and the reason why washing your hands before eating is good for you. Instead, Jesus criticizes the Pharisees for following that custom.

Mind you, a custom that according to these Christian apologists, is divinely inspired and perfect.

Jesus concludes his criticism with this:

¹⁴ Again Jesus called the crowd to him and said, “Listen to me, everyone, and understand this. ¹⁵ Nothing outside a person can defile them by going into them. Rather, it is what comes out of a person that defiles them.”

Again, this is a missed opportunity to explain why dirty hands and dirty water cause disease. Instead, Jesus criticizes the Pharisees for following such rituals.

Jack Chick's views are not as fringe as you might think

Most non-Christians love to laugh at Jack Chick's tracts, and how utterly detached from actual society he seems to be (especially given that he is an American and lives in the United States.) It can be hard to believe that anybody would think like him about our society.

For someone who has never belonged to a Christian denomination of that kind, the views he has of our society may feel completely crazy and fringe, but he is not the only one who believes these thing. There are many Christian denominations, especially many of the so-called charismatic ones, where many members do indeed believe most of those things. In other words, they really do believe that the vast majority of people, even in the US, are hard-core militant atheists who hate God and are really aggressive about it, who are basically possessed by demons (often literally), and even mentioning religion to them hits a berserk button. They honestly believe that Christians are widely discriminated against and persecuted, and that even mentioning God or the Bible could end up badly (but that doesn't stop them from doing so, of course, because they are true believers and would gladly become martyrs for their cause). They constantly tell between themselves stories about how Christians are persecuted, imprisoned and even killed in other countries, etc. They also believe, like Jack Chick, that most people have never even heard of Jesus or the Bible, and that preaching the gospel to them is like a magical incantation that either converts them on the spot, or enrages them into demonic furor.

These people live in some kind of strange societal bubble, where they more or less subconsciously shut off their own perception of the real world. They pretend that the world they see and live in is something that it isn't. They basically deny their own senses and experiences, and want to believe something that just isn't there. Mind you, most of these people are not living in some secluded cult isolated from the outside world. Most of these people are everyday citizens, working and living like everybody else, interacting with people like everybody else, seeing the society that surrounds them every day... and yet, they still believe those things, against all evidence and personal experience.

It's hard to believe this unless you have been one, but it's true.