Reference for Shabbat 33:1
אקפח את בני שזו הלכה מקופחת ששמע השומע וטעה האיכר עובר ומרדעו על כתפו ואיהל צדו אחת על הקבר טימאו אותו משום כלים המאהילים על המת
May I bury my children,<span class="x" onmousemove="('comment',' Lit., 'may I cut off my children that this halachah is cut off'. ');"><sup>1</sup></span> if this is not an erroneous <i>halachah</i>, for the hearer heard [a ruling] and erred [therein]. [Viz.,] a peasant was passing with an ox-goad on his shoulder and one end thereof overshadowed a grave, and he was declared unclean in virtue of [the law of] utensils which overshadowed the dead.<span class="x" onmousemove="('comment',' I.e. any utensil which overshadows the dead becomes itself unclean, whatever its width, and the peasant was declared unclean for the same day till the evening because he was actually carrying and in direct contact with this ox-goad. But one of the disciples who heard this ruling erroneously imagined that he was unclean in virtue of the law stated in n. 7. involving an uncleanness of seven days, and thus drew a false conclusion. ');"><sup>2</sup></span>