Your right, scripture doesn’t explicitly tell us about laodiceas water source. What scripture does say, is that Christ wanted the laodiceans and their works to be hot or cold, but not luke warm.
And what does the archeology actually show?
It shows that the aqueduct system was the same there as in all of the other Roman cities of the Levant, that the water was not - as is claimed - brought directly in from the sources mentioned, but from a different direction, and also that the water of Laodicea was considered "medicinal".
It also shows that, among the well to do in mountainous Asia Minor, where mountain snow was available not all year, but during significant parts of it, that hospitality involved warm drink, or chilled drink. Room temperature (warm and fetid) drink was not a very hospitable thing to offer, if you could afford better.
So the hot/cold/lukewarm reference was very probably not some deep secret knowledge that only locals of Laodicea would understand, because of some mythical aspect of their Roman aqueduct system that was particularly different from that of the rest of the Roman cities around the region, but because of a cultural hospitality that people generically understood.
In the age before electrical refrigeration, to prepare a cold drink did require some expense and effort, but was done. And of course heating drinks always is done.
So, the bottom line: there's nothing wrong in this case with reading it exactly as written and understanding it as written, with references to modern hospitality: you had a visitor hot coffee or cold water, but you don't hand a visitor a can of Coke that sat out all day and is lukewarm. It's nasty and it's not showing any love or desire to refresh the weary traveler.
One CAN engage in discussion of the water system of Laodicea, that the particularly MIGHT have made the story particularly pungent for the people of that city. But when one does, one had best temper that discussion with the likelihood that, actually, the archaeology doesn't really support there having been anything particularly special about the public water system of Laodicea compared to any other Roman city around the area.
However, when one takes the additional step of drawing one's self up into the supposed "special knowledge" of additional outside study, to start telling people that they don't know what they are talking about and have no authority to comment on the passage unless they know this special additional knowledge - well, then they expose themselves to being called out on the fact that the "special knowledge" is very likely untrue from an archaeological standpoint, and that THEREFORE the claim to superior teaching authority on its account actually reveals and inferior degree of teaching authority, because the teacher of the false knowledge did not take the time and care to go research it WELL before making the lack of that knowledge a point of harsh criticism of those who do not possess it.
It isn't the fact that it's true or not - it's the assertion that if one doesn't know this truth one is ignorant and can't teach: THAT is the part that needed to be poked at. Really, the waters of Laodicea were not so noticeably icky and lukewarm that the ancients commented on it, and they weren't piped directly from the sources that some people who want to make too strong a religious point assert they were.
Had the religious point been made gently, it wouldn't have been necessary to flip over the table, but it was made strongly, aggressively - if you DON'T know this special knowledge about the waters of Laodicea, then you cannot speak on the Scripture!
That was the tone.
Trouble is, if you examine the actual archaeology, there wasn't anything special about the water supply of Laodicea, so the assertion that this absolutely refers to THAT - and that one cannot speak unless one knows that - is a teaching based on a fable. And the embarrassment of discovering that SHOULD sting enough that those who make the bold "YOU HAVE NO AUTHORITY TO SPEAK!" arguments should learn from that to not do that again until they have made a THOROUGH (and skeptical) investigation into the supposed "special knowledge" that supposedly disqualifies everybody else from speaking or expressing an opinion.
Because, pretty much, if the "special knowledge" turns out to NOT BE TRUE, than the one who claimed the authority to speak WITH authority really has LESS authority than the rest, because he claimed stuff that isn't true as the BASIS for a teaching.
Christians like to assert authority over others. Most of it is baseless.
