Witness testimony IS a justification for belief. Witness testimony may be the end of our verifiability, for instance, if the murder weapon is destroyed we may have to rely solely on witness testimony. The witness testimony IS the verification. So it may be fuzzily verifiable, but it is verifiable. Similarly, if many witnesses have written about what you might call a "religious" event, your reason for assuming they are lying is simply that you've already decided they are lying, not because you have some other evidence to the contrary. Their testimony IS the verifiability. Your job is to say why you would disbelieve witness testimony. Either they are telling the truth or they aren't, and the general assumption for a disparate group of witnesses telling roughly the same story is that they are probably telling the truth. I say roughly because if they told exactly the same story you might be able to assume that they made it up and are got their stories straight before hand. Regardless of whether you believe them or not, anyway, they are a source of authority on the subject in that they claim to have been their and are reporting on what they saw.
Except psychologists and other experts have known for years that witness testimony is not very reliable, and should only be used as a last resort in lieu of other facts. It's trivial to prove this. Consider magic tricks, or this popular test. Reality and what a witness would swear to are vastly different. This is even neglecting the idea of mass hallucination or suggestibility.
This is not to say that the witnesses are necessarily lying — just that they are, instead, fundamentally unreliable for reasons that has nothing to do with the personal attitude of a witness and instead has to do with basic human psychology and attention.
Thus, because extraordinary claims must require extraordinary evidence, claims of the supernatural require evidence that is extremely compelling. Citing a single reference that compiled a set of stories of questionable authorship spread over decades or centuries following an event at such a time that the common writing down of mundane records was uncommon, and thus subject to decades or centuries of the telephone effects, is absurd.
If you accept such cherry-picked witness testimony, there is no reason to deny the witness testimony of priests of Thor, Horus, or Zeus. There are hundreds of them, also in historical records, and many of their contemporaries claimed direct observation of the deities or their effects. I apply the same standard to modern religions as I do to the ancient ones. Anything else is hardly a consistent position.
Unless you're planning on sacrificing a lamb to Zeus today?
Validation does not come from verifiability, a valid argument is one where the conclusion follows from the premises. I can make valid arguments that are completely unverifiable if I just assume crazy unverifiable premises.
In which case, you may have a "valid argument" but the whole construct is still not verifiable and thus, in a greater sense, the whole construct is invalid. My point still holds.
I've been told by authority that I consider reliable that it is true, and the original point of my post stands, this is often enough.
This might fly as long as you never actually have to discuss the subject or things related to it. As soon as you do, it's really just intellectual laziness to rely on another's conclusion of third-party data. But if the topic must be considered in any fashion, really, the onus is on you to research your position and verify it. Otherwise, you get things like this intellecutal laziness which plagues public opinion. It's the same reason "Electromagnetic Radiation" is scary to the "common man" and there can be an uproar over WiFi causing cancer. They take "radiation" from loose discussions among non-experts and apply a bad connotation to it, and use that information as "good enough" to extrapolate further information.
It's intellectual negligence, plain and simple.