Reference for Chullin 227:55

בחלב אמו אין לי אלא בחלב אמו

Then for what purpose do I require the verse: 'In its mother's milk'?<span class="x" onmousemove="('comment',' Since this verse is repeated thrice, one clearly serves for its own purpose, another to include the cow and ewe (the teaching of the first Baraitha q.v.) , but the third is indeed superfluous.');">²⁵</span> - It is required for what has been taught. It is written: 'In its mother's milk'. We know [that it is forbidden] in its mother's milk,

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