Not necessarily. If you know a person well enough, you can know if they are lying. I have known when friends have lied and tried to deceive me in doing so. Plus, you don't need to even know a person that well. For instance, on this website I often ask questions of people and their response is deliberately avoiding the purpose of the question. When this happens over and over as I ask the same question, it becomes apparent that they cannot really give a truthful answer to the question because they are afraid of the implications of doing so.
As well as this, knowing holiness is to be able to recognise a holy person. It is the holy spirit that testifies to the truth. People who are deceitful do not exhibit a holy spirit, because deceitfulness is sinful. Jesus said this too: Your eye is like a window for your body. When your eye is healthy, your body is full of light. When there are no dark corners within you (that means to be actively repentant - having no sin in you), then your face glows as though a powerful beam of light is shone on it. You can read of this happening to Stephen when he chose to bear witness to the truth before he was dragged outside and stoned. Holy people can be mistaken though, and that can cause them to be wrong. But the thing is, that the holy spirit is consistent. It has a certain gracefulness about it, that makes it so obvious that the person is not acting in deceit.
You can notice that the bible doesn't make out that they do. But, it makes a claim that Moses had this experience. I am not worried to believe that it was a hallucination. But what I see about this, is that seeing it is not normal, does not make it impossible that Moses had this experience, and the context and tone of the claim is given such that it does certainly appear that the reader is meant to believe it really did happen. I can see a distinct difference to the way that bhstme stated he had been abducted by aliens two nights ago. I could see that he was making that statement deceitfully. Mostly, it is because I knew his motives, and that provided context for me to reliably view it as not being a genuine claim of truth.
Yet, it becomes this question again: - is it
possible that the man Moses really did have this experience. I think it is. But I think that is probably one of the most modest examples you can deliver, as I know there are examples in the bible that I find impossible to imagine.
I think you are wrong to have said this, and expected me to agree or to be wrong not to agree. It's as though you think I cannot possibly be right to say that God can do that if He wants to. This concept of God that you and I have central, is one that is attributed to creating everything when it wasn't created in the first place. Plus many other things. It's an immensely powerful being, and if you are addressing me knowing me to be someone who makes a base assumption such a being can possibly exist, and is most likely to exist, then this comment of yours seems to not have enough effort applied, if your objective is for us to find some agreement. Otherwise, if your objective is something else, ok maybe this comment would do that.
I know they do this sometimes. Can you offer some practical feedback for me?

I like that
Ok, sure. So that would show me that people do not love me as I love myself, and possibly they could have good reasons; and that people are not as honest as I would be. But why suggest that my feelings are causing some delusion in that? Isn't it somewhat just as fair to say that I simply had different understanding of their views than they did?
He has spoken to me in all those ways, FWIW.
Do you think there was some jealousy, or pride, or insecurity going on behind all that dissension? Don't you think that if people were truly at peace with their self, their security in God, then they would love their brethren and support them, being confident in their self, and manifesting unity? Does it sound to you as though Galatians 5:20 describes the same things that you saw?
I could. But as yet I haven't seen an alternative view than the one I am viewing, and that seems to be quite well detailed. Sure though, do let me know if you are able to provide some alternative view, as I also asked Aelred a few posts back. It wouldn't be wasted if it is useful.