Does the Torah prohibit insect infestation that is only discernible with a strong magnifying instrument. Does the Torah require checking foods for infestation which is not visible to the naked eye. Did they have magnifying instruments in the time of Chazal.
1. They didn’t have magnifying glasses in times of Chazal.
2. The Torah does note obligate checking for infestation not visible to the naked eye (of somebody with good eyesight).
3. The Torah does not forbid insects unseen to the naked eye (or else it would be forbidden to breathe).
Yet, there are cases where a speck is seen to the naked eye, and some write that in such cases one must discern what it is with a magnifying glass.
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