A question, if strong drink was only 15% alcohol and below in biblical times, how was it used as a starter fluid? I believe you need much stronger alcohol to light a fire, no?

From a recipe:

As soon as the mushrooms are colored add the marsala wine.
Caution: the Marsala wine is flammable so watch for spills.

Legal description of Marsala wine:

"Marsala" wine, over 14% vol. alcohol, in containers holding 2 liters or less

So it appears that at the high end (strong drink), naturally fermented beverages are flammable. I don't know without additional research exactly were a flash point is reached.

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