Many people go to church or assemblies of some kind and hear things taught by the speaker and believe them at face value, while it is understandable because many teachers and pastors are both well respected and well versed in scripture.
However a good teacher or pastor will encourage their listeners to study for themselves what they teach, (if they don't you might want to find out why) remember we are all part of the human family and no matter how much knowledge we have we are capable of error.
That said I would like to draw your attention to this: when someone presents a doctrine or concept that sounds strange or even wrong because it differs and may well be directly opposite of what you have been taught, this in itself is not sufficient reason to reject it out of hand, now please don't misunderstand, there are absolutes and some things are not to be challenged as they are well established in the sacred word, however to simply reject a thing without seeing for yourself (in scripture) where it comes from and if indeed it passes the test of scrutiny based on the great standard for all doctrine and instruction in righteousness, (2 Tim. 3:16) if it is truth it will stand scrutiny and mans opinion of it (no matter how learned that opinion may be) if it be error it will surely fall, but to reject it without seeing for yourself is both foolish and even shameful (prov. 18:13) so the next time you hear something "strange" take the time to check it out first, it can only bring a positive outcome because one of 2 things will happen: 1 what you did think was truth will be firmly established and 2 if it is error you will be free from it. Shalom....