Hi,
In the answer about electric and gasoline cars, you explained that internal combustion is not halachic havarah, which concerns a flame or glowing coals. Could you explain why the spark that ignites the fuel in a gasoline engine does not count as havarah on Shabbat? What is the halachic distinction between that spark and lighting a flame, and which sources establish it?
The Torah’s מלאכה of הבערה refers to אש in the halachic sense, principally a שלהבת, an actual burning flame, or a גחלת, a burning or glowing body.
That is the world described throughout Chazal. The Rambam, Hilchot Shabbat 12:1, gives the normal examples:
“המדליק את הנר או את העצים… הרי זה חייב”
and then discusses heating iron until it becomes a glowing גחלת as a תולדה of מבעיר. In other words, the classical מלאכה involves something actually burning or glowing as fire.
A spark by itself is not necessarily the same thing.
This distinction continued to be discussed by the poskim regarding sparks. The Pri Megadim understood that sparks that have no substance are not necessarily מבעיר מן התורה. Rav Shlomo Zalman Auerbach explains the idea that a tiny individual spark may not yet have the halachic status of אש at all, particularly where it has no substantial heat or continuing existence.
That is the basis of what I wrote regarding a gasoline engine.
The spark plug produces a momentary electrical spark which ignites the compressed fuel-air mixture. There is then an extremely rapid combustion event in the cylinder which produces pressure and drives the piston. But there is no continuing שלהבת that remains burning, and there is no גחלת, a burning or glowing object, which continues to exist. Each event occurs essentially instantaneously and disappears, and the process begins again in the next cycle.
Therefore, my understanding is that we should not automatically take a modern scientific process called “combustion” and assume that it is identical to the Torah’s מלאכה of הבערה. Scientific terminology and halachic categories are not necessarily identical.
The question is not whether chemists or engineers call what happens in the cylinder “combustion.” The halachic question is whether what has been created is the אש of Chazal, meaning a שלהבת or גחלת of the type that constituted הבערה in the Mishkan.
In my view, the momentary spark and instantaneous combustion occurring inside an engine do not create that type of halachic fire. They are a modern mechanism producing a rapid series of pressure-producing combustion events, not the lighting and maintaining of a שלהבת or גחלת contemplated by the מלאכה of מבעיר. My father agreed with me completely.
Of course, this is an application of the classical definitions to modern technology. You will find contemporary poskim who classify internal combustion differently. But the basis for my position is not that gasoline somehow does not undergo combustion. It is that not everything modern science calls combustion necessarily falls within the Torah’s specific category of הבערה.
Thank you Rabbi for explaining the distinction.