Jesus turned barrels of water into wine, and good wine at that. Not a drop or two, but large pots, and in only a moment. The details might be important.
Jesus told them, “Fill the jars with water.” So they filled them to the brim. Then he told them, “Draw some out now and take it to the headwaiter.” So they took it. And when the headwaiter tasted the water that had become wine…
Evidently, Jesus never touched the jars. As soon as they were filled, the water in them turned to wine (though it’s possible the water turned to wine in the ladles). The time this took must have been short. A moment or two, tops.
This happened, so it had to happen some how. The question is how? If we have any physicists or chemists in the audience, perhaps they might take a guess. (If you say it didn’t happen, then suppose it did arguendo. Do not go on about how it didn’t.)
One answer, and a right answer, is “Jesus is God, and God made the world, so using these same sorts of powers, God turned the water to wine.” While this is a right answer, it does not answer how.
Knowledge of the “standard model” used in physics suggests tremendous amounts of energy are required to transform elements, and that mass and energy are in some sense equivalent, so that if any of the mass of water and trace elements in the jars was transformed into the chemicals (including ethanol and water) which made wine, more generated power available in the whole of the world at the time would have been required.
Perhaps a “spherical cow“-type analysis can provide insight, not for the quantification per se, but to gauge the size of the problem. Even if that is forthcoming—knowledge of the size of the energy required—a mechanism still has to be posited. Some kind of map that says “push these water molecules together, supply them with such-and-such momentum, etc. etc. etc.” And then you’d have to figure how some ancient peoples who had not yet harnessed electricity carried the thing out. No easy job, that.
At the other end of it, we know that such a thing must be possible because, of course, it happened. Transforming water into wine is therefore doable. But because it is doable, and because we might figure out how it can be done, at least theoretically, that does not mean that Jesus did not do it, because of course he did.
Knowledge of how an event might be caused is therefore no bar to the event being miraculous, if we accept (loosely) as “miraculous” a direct intervention by God on the secondary causes of the world. But knowledge of how an event might be caused is not equivalent to knowledge of how it was caused, though the two might overlap. There is more than one way to make wine.
Suppose we have a physical model and a means for the wine creation. It is clear, based on all evidence, that the means was not present 2,000 years ago if the means were some sort of electronic apparatus. Of course, it could be that some machine could exist that could be made of parts and know-how available then but that we in our day will never dream of. And that this apparatus could have been used. Point is, just because we (or you) cannot think of how a thing can be done, does not logically imply that the thing cannot be done—especially in the face of the thing having been done.
To summarize: the water-into-wine is a miracle for two reasons. One, Jesus did it. Two, we think it impossible, given our cumulative knowledge, that such a thing could have been done without God in that time and place and circumstance.
All this is in contrast to mysterious medical cures, which are often put forward as God-caused miracles (which I assume many are). A physician writing in the New York Times said she “examined the files of more than 1,400 miracle investigations — at least one from every canonization between 1588 and 1999…stories of recovery from illness or injury, detailing treatment and testimony from baffled physicians.”
The difficulty, which is clear, is that bafflement is epistemological. As medicine advances, bafflement recedes, and so do miracles, if all that is required for a miracle is knowledge of a possible how (explanation). What was taken as a miracle last year, and certified as such, could be uncertified once it is learnt that, say, enzyme X was present when it was not known earlier that enzyme X was the cure.
This is why the miraculous cannot be based solely on science and must require faith.