Pesachim 10a, b

Our Sages examine a number of cases of certainty/uncertainty to clarify when we are to do additional searches for leaven.  As well as another look at mice possibly carrying leaven into homes and possibly dropping or trading or eating that leaven, the rabbis consider analogies regarding ritual purity. 

We begin with some new information (for me). If a person walks in a field in spring (when one should not walk to save the new growth) and then in a valley that might be impure (ie. may have a corpse buried in it somewhere), that person is considered to be ritually impure.  This is because a valley during the rainy season is thought to be a private domain, and in cases of uncertainty regarding ritual impurity in private domains, one is ritually impure.  However, we also learn about chazaka, where one who has the presumptive status of ritual purity should retain that status in times of uncertainty.  How does this help us?  Just wait.

The rabbis continue with a conversation about money.  If second-tithe money (for the priests) has been added to or taken from, that money is considered to be non-sacred.  It loses its sacred status because of the possibility that it might now be intermingled with impure coins.  I should be clear - there is much conversation about these 'answers'.  The rabbis debate about the mice, the person walking during the rainy season, the money.  Sometimes they disagree in principle and sometimes they disagree on smaller points.

The rabbis continue this line of thinking with a discussion of crumbs, axes, and loaves that have been moved from one place to another.  Generally speaking, the rabbis agree that the house needs to be searched again only if it is likely that leaven is in the home or that ritual impurity has been contracted.  We are learning about cases of uncertainty.  Of course, the search for leaven is overflowing with uncertainty, as is the clean-up for Pesach.  So our rabbis look to other cases of uncertainty to guide their decisions.  However, I would argue, the search for leaven is so specific, so particular... can other halachic imperatives offer any true guidance?

Interestingly, the end of today's daf focuses more on the larger "why?".  A last mishna tells us that the rabbis debate about how many opportunities exist to search for leaven.  Rav Chisda and Rabba bar Rav Huna tell us that the three searches for leaven correspond to our three Torah instructions: 

1) "Matzot shall be eaten for seven days and no leavened bread shall be seen with you, neither shall there be  leaven with you, in all of your borders" (Exodus 13:7)
2) "Seven days shall there be no leaven found in your houses (Exodus 12:19)
3) "Seven days shall you eat matzot, yet on the first day you shall remove leaven from your houses" (Exodus 12:15)

The rabbis argue about whether or not there should be additional times to search for those who do not search during these opportunities. 

I take from this that our rabbis are so intent on interpreting the Torah - and so eager to justify the already-established traditions of the community - that they create laws that are stringent rather than lenient.  And by their own admission, rabbis agree that rabbinic halacha should be lenient.  Thus any opportunity to interpret Torah law with creativity is an opportunity to reestablish power and influence over generations of jews.  Well, I'm just working through this idea... more to come, I'm sure.