hello99 -“Actually, your quote is selective and out of context. Reb Moshe in 4:60 was only lenient on a Shabbos clock, not a true Amira l’Akum. Furthermore, he explicitly differentiates between lights where there is already a Minhag to be lenient, and he is not capable of forbidding it, and other appliances. He clearly writes that it is wrong to rely on the Itur and the Minhag in Europe was to be stringent.”
You are misconstruing it.
Quote: “And it’s Mashma (from the Rema) that in a case of Tzorech Godol it’s (Ameira L’acum) is Mutter. So even though it’s fitting to be Machmir and in our community in Europe we were Machmir, BUT since there are many that were Matir (Ameira L’acum) and this was the Minhag in many places -I’m not going to Assur time clocks where they are already using them.”
You see clearly – he didn’t have a problem with people being Somieach on Ameira L’Acum B’mokom Tzorech Godol. He personally had the Minhag not to be Soimeach on this Rema, but he didn’t think people who were Somieach on it were being Oiver an Issur D’rabbonon. If he did, he never would have used it to be Matir time clocks. He held at the beginning to use time clocks (on Shabbos) is definitely Ossur. So what changed by lights? Why can time clocks be used to turn on & off lights? Because some Avaryonim acc. to you, used a Heter from the Rema which you can’t be Somieach on? So you see clearly R. Moshe didn’t want to use this heter himself, but he used it to be Matir time clocks. I’ll repeat – he must of held there is something to this Heter and that’s why he said you can use time clocks for lights.
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