Reference for Chullin 200:28

וקשיא לן

- Notwithstanding the fact that the prohibition of uncleanness comes first the prohibition of the nerve can indeed be superimposed, because this latter prohibition is binding even upon the sons of Noah.<span class="x" onmousemove="('comment',' Where the later prohibition is more stringent in that it applies to a larger number of people than the existing prohibition, it can be superimposed upon the latter. And the sciatic nerve (as stated by R. Judah in the Mishnah) was forbidden to all the sons of Noah, for it was declared forbidden even before the giving of the Torah at Sinai to the sons of Jacob who at that time were deemed sons of Noah.');">²⁰</span>

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