Talmud for Pesachim 140:1
במרובה מנא ידעי
<br> in large [portions]. How can we know? - Rather it means that it came in uncleanness. Yet after all, how could they know? - The nasi had died. When did the nasi die? Shall we say that he died on the thirteenth, then why was it necessary for the owner to perform tebillah for the knife? Again, if he died on the fourteenth, wherein does the knife differ, that [we say] he [its owner] gave it tebillah, and wherein does the chopper differ, that [we assume] he did not give it tebillah? - This arises only when the nasi was in a dying condition on the thirteenth. As for the knife, [concerning] which [there is] one doubt, he would give it tebillah [on the thirteenth]; the chopper, [concerning] which [there are] two doubts, he would not give it tebillah.