Confirmation bias is what all religious people suffer from when it comes to their religion. They seek information that confirms their beliefs (their religious works) rather than judge different sources of information on their merits. Take for example the issue of where did humans come from.
The Bible, Quran and Torah all claim we popped full formed into existence starting with Adam and Eve. According to religious scripture this happened around 6000 years ago. These books were written by ancient shamen that didn’t know what electricity was, didn’t know the earth rotated around the sun, didn’t know why the sky is blue, didn’t have computers , no internet, no microwaves, and so on. By today’s standards of science they were all crackpots.
Then we have modern palaeontology, physics, astronomy, biology, chemistry, geology and other scientific fields that all came to the conclusion that what actually happened is we evolved from simpler life forms. We have millions of pieces of evidence evolution happened and that the earth is a lot older than 6000 years.. Fossils of more primitive humans evolving over time. We have radiocarbon dating that identifies approximate dates of physical specimen. We can determine by the speed of light alone that the universe is at least billions of years old. We have observed evolution with experiments in bacteria, Its even in our very DNA that connects us to all other lifeforms on this planet. This reseach is done by individuals that have spent their entire lives studying a specific topic who built on the research of other people who spent their entire lives studying the same topic. And they are ALL in agreement on evolution. If we take way the religious crackpot element, there is literally 100 percent academic agreement that evolution happened. We call it a “theory” out of convention but in practice its a fact.
In other words the Bible, Quran and Torah… all lie. Some ancient bullsh-tter made up the story and all three religions adopted the same bullsh-t. A reasonable person would ask the question if these are indeed holy books that speak for some alleged super space snuffleupagus.. why would they lie on some detail so important as our orgins? And the rationale conclusion is they are not “holy’ books. They are mythology books like ancient of stories of mithra, zeus and so on. They mix fact with superstition which fools the usually well meaning but naive into following them because their parents did.
And the followers once indoctrinated by their parents and peers usually spend the rest of their days trapped in their mythologies because they read the crackpot sources that confirm their beliefs and brush aside the far more credible sources that contradict their mythologies. This is confirmation bias.