How do you know?

Some Xians claim that god speaks to them or that they feel god's presence. OK, so how do you know that it is god's presence? In order to know that it is supernatural, that would require that one be able to eliminate all possible causes, both known and unknown - good luck with that.

But, let's say that some supernatural entity is talking to theists. How would a theist know that it is god talking to them and not some other entity? Many Xians believe in Satan and demons, and they automatically assume that anything that brings them closer to god is from god and anything that leads them away from god is due to Satan or his demons. This presumes that the theist knows and understands what leads to god, however. So, for Xians, what if Allah is the one true god? Then, demons might be leading you to Yahweh and they would be leading you away from the one true god and towards your eternal torment. How would one know?

There are, of course, other problems, like why god would allow demons to lead humans (that he supposedly loves) to their destruction, and the inherent confirmation bias of having one's personal views confirmed automatically leading to god, as well as the count the hits and ignore the misses inherent in such an exercise. In short, claims about hearing specific gods, etc., are patently absurd and useless.