While an open mind involves the mentality that you're willing to "question everything", that does not mean that the answer to all that questioning is that 100% of your knowledge must be discarded daily.

A truly open mind has various hypotheses and mental models that they are willing to change when evidence suggests that the hypotheses as been disproven or the mental model is not accurate. If you are also aware of your tendency to fool yourself, to resist even necessary change in thinking or action, then that is even better. If you understand critical thinking and how to identify and avoid logical fallacies, better still.

The religious are so accustomed to special pleading and confirmation bias that they often don't realize that their beliefs, if held consistently, actually ARE racist, otherizing, and/or cruel. They have a carefully cultivated self-image as kind, well-intended people, that blinds them to the essential arrogance and self-centeredness and cruelty of their beliefs. So I don't think it's a question of lowing the bar just far enough to belief their faith claims but not so far as to be a dick; their faith claims are already dickish, as is their god.

I'd like to thank all of the commenters on this post. All of your posts were well thought out. Back in the day, the religious types would reply with something along the lines of "That's stupid," which didn't address the issue at all.

I saw an advertising board at a church while I was driving , it stated an open mind let's the devil in.
I had nice laugh.

I don't agree that an "open mind" would concede that everything they learned previously was wrong, but having an open mind would at least be open to the possibility that it could be. IMHO

There's always the saying don't be so open minded that your brain falls out

That defines gullibility, not having an open mind. Or are you saying they are the same?

Eastern philosophy uses the term "beginner mind". Listening with the mind cleared of past assumptions and weighing new concepts against each other to form a body of knowledge as they are presented. The result of this listening process can then be integrated with your previous knowledge. This allows for the collection of ideas and evidence in a non-judgmental way so as to hear all of the information being presented. This is only a process for listening and learning new knowledge. The assimilation of the knowledge can then be filtered through your own prejudices, values and experience to create your own understanding of that knowledge. You don't give up anything. You make your own judgement based on more complete information which should result in a better learning experience.

Somehow, I perceive that 'open mind' concept, as don't lock your ideas up so tight, that you can't take in new information!