Q&A: Water Left Overnight
Water Left Overnight
Question
Apparently nowadays there is no need for “water left overnight,” because that was only based on their worldview about where the sun is at night.
It should also be noted that this is not a law given to Moses at Sinai, as is evident from the Talmudic passage (Pesachim 42a). Rather, it is only a technical requirement.
“Rav Yehuda said: A woman may knead only with water that has stayed overnight. Rav Matna taught in Papunia; the next day everyone brought their pitchers and came to him and said to him: Give us water. He said to them: I meant water that had stayed overnight in the house.”
Answer
I allow myself to guess that there was a question here, although there is no hint of one in what was written. I can even guess what the question was: whether in my opinion one can really dispense with water left overnight.
In principle, certainly yes, but note that there is an aspect here that you are ignoring: suppose the water in the morning is warmer for some other reason, not because the sun is frying it from behind during the night. Still, if factually it is warmer, that is enough to follow the instruction of water left overnight (that is, to let it sit overnight). The scientific explanation is not relevant to the law itself.
Discussion on Answer
So put it there. This has nothing to do with mistaken scientific knowledge.
Nowadays, when you can measure the water temperature, why should I care whether spring water is warmer in the morning and why?
We’ll draw it, put it in the fridge for an hour, and that’s it.