Pesachim 4B

לאו משום דחזקתו בדוק, דקסבר: הכל חברים הם אצל בדיקת חמץ. דתניא: חבר שמת והניח מגורה מליאה פירות, אפילו הן בני יומן ⁠— הרי הן בחזקת מתוקנים.

Isn’t it due to the fact that the presumptive status of the house is that it has been searched, as this tanna maintains: All are considered ḥaverim with regard to the search for leavened bread? A ḥaver is one with the presumptive status of trustworthiness with regard to a given matter, e.g., ritual purity and impurity, tithes, etc. In this case, since everyone has ḥaver status with regard to searching for leaven, everyone is deemed trustworthy to have performed the requisite action. As it was taught in a baraita: With regard to a ḥaver who died and left a storehouse filled with produce, even if the produce was there only that day, the fruit has the presumptive status of produce that was ritually prepared, i.e., tithed, as there is no doubt that the ḥaver tithed his produce before he died. The same applies to the search for leaven: All are considered ḥaverim and are believed.

וממאי? דילמא שאני הכא, משום דקאמרי הני. אטו אמירה דהני מידי מששא אית ביה?

The Talmud challenges this claim: And from where can this be proven? It is possible that in general a house does not have presumptive status that it was searched, and perhaps it is different here, due to the fact that these people, e.g., a woman, slave, or minor, expressly stated that they conducted the search. Perhaps that is why the house is considered to have been searched. The Talmud rejects this contention: Is that to say that there is any substance in the statement of these people? Since the testimony of all these is disqualified, they lack credibility, and their statements are not reliable. Instead, the reason that there is no need to search the rented property for leaven must be because of the presumption that it has already been searched.