I thought you can only stay 2 days without water? I couldn't imagine that. That sounds dangerous, you could easily fall into psychosis. If you mean alcohol yes, but water no. Water is healthy
This website is concerned about your life, health, and safety. So, certain moderators, such as paranoid android, do not recommend it nor agree to it (I think). And they are, of course, concerned about the legal situation of bluelight, possibly getting in trouble for recommending something of a 2 day or 3 day fast without food and water. And possibly (not to be rude or hurtful) ego could have some say. I'm pretty sure they're above that fast in their minds, but still some machismo or glory (or vainglory) in them may cause them to also be against it. I mean that kindly.
"And he was three days without sight, and neither did eat nor drink" (Acts 9:9).
"Go, gather together all the Jews that are present in Shushan, and fast ye for me, and neither eat nor drink three days, night or day: I also and my maidens will fast likewise; and so will I go in unto the king, which is not according to the law: and if I perish, I perish" (Esther 4:16)
Peace and Love! And God bless you all!
P.S. They, which ever of them don't agree to it, may have some insecurity or fear because of the length of the fast, and possibly they may not feel they can do it, although it is possible for them (to do so). They do have the willpower. Truthfully, I would have liked to do 4 days and 4 nights or longer. In a better environment (away from negative people or energies, especially neighbors) I would do a longer fast. Actually I would pray long hours and do many rituals to GOD, to his angels, etc.
