A great deal of effort is put into ‘teaching’ – some would say brainwashing – kids into a particular religion. Personally I find this as obnoxious and disgusting as I would the forcible indoctrination of children into the Ku Klux Klan and potentially even more damaging in the long term.
Whether it’s ‘This is how I was brought up’ or ‘William Lane Craig says so’, the argument is basically the same. Someone that you, perhaps ill-advisedly, trust has told you X, therefore you believe it and them.
This is a fallacy known as the ‘Argument from Authority’ and it’s fallacious because simply because someone is in a position of authority or is right about something else, doesn’t mean that they’re right about this.
Theists occasionally like to turn this around and say ‘Well, you haven’t done all these scientific experiments yourself, you’re just trusting the scientists’.
Science constantly tries to disprove itself, it is subject to peer review and repeat experimentation. Over the last few centuries it has established a great track record of useful discoveries and of weeding out issues and falsehoods. The exact opposite of what’s happened with religious claims. Additionally, science rests on evidence, not the authority of the person presenting it and – perhaps most importantly – science has practical applications, which wouldn’t work if the theories were wrong.