How easy is it to fool people?

Whenever I debate with theists, I've come across a rather….intriguing argument. One of the main reasons I argue against the validity of biblical claims is because of how untrustworthy the sources can be, especially considering that more than half of it contradicts reality (ie how jesus walked on water). The now-common counterargument I've seen is that 'so many people saw the event happen, and you can't fool thousands of people'. Although sometimes this argument can invoke the fallacy of composition, there are much more important flaws concerning this type of sloppy reasoning to supply credibility to evidence. My rebuttal to this counterargument: 1) People can be easily fooled – regardless of how 'advanced' a society might be. 'Common sense' is a completely unreliable way of determining fact 2) High illiteracy and a lack of proper scientific understanding affects how a person may see and understand the world around them 3) The fear of the unknown and the desire to overcome problems for which no current solution is available leads people to jumping to the easiest and most fitting solution (in this case religion) 4) Balance of probabilities – which is more likely: the laws of nature and of science as we know it to have been broken IN A WAY THAT FAVOURS THE THEIST'S ARGUMENT, or that they got the wrong impression of what actually happened. This is NOT meant to be proof disproving the claims of theists – instead this was meant to be a reasonable objection to the 'evidence <b>…</b>