Reference for Chullin 66:5

והא נגיעה היא מדקתני

The Sages however regard Second Tithe to be affected.<span class="x" onmousemove="('comment',' Lit., 'they forbid in the case of Second Tithe'. Presumably the Second Tithe becomes unclean in the third degree by contact with that which was unclean in the second degree. On this assumption our Mishnah can be interpreted as dealing with animals bought with Second Tithe money.');">⁴</span>

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