Verses Lv14-33:37,46 discussing the examination of leprous houses states
- And the Lord spoke to Moses and to Aaron, saying,
When you come to the land of Canaan, which I give to you for a possession, and I put the disease of leprosy in a house of the land of your possession;
- And he who owns the house shall come and tell the priest, saying, It seems to me there is a disease in the house;
- Then the priest shall command that they empty the house, before the priest goes into it to see the disease, that all that is in the house be not made unclean; and
- afterwards the priest shall go in to see the house;And he shall look on the disease,...
- Moreover he who goes into the house while it is shut up shall be unclean until the evening.
Rashi uses the straightforward Non-verse logic rule.
If you didn't do step #3 above - emptying the house - then after step #4 - the
examination and declaration of the house as unclean - all the contents of the house
become impure, as indicated in step #5. It follows that the reason for step #3, is,
as the Bible explicitly indicates by the underlined phrase,
that all that is in the house be not made unclean.
In other words even though leprosy comes for the sin of slander nevertheless the Torah
had pity on the monetary assets of the slanderer and saved them.
Advanced Rashi: Rashi uses more advanced techniques to show that when
the Torah wished to prevent declaring the house contents impure the emphasis
was not on ordinary utensils - which if made ritually impure can be re-purified by
immersion in a Mikveh body of water - but on clay utensils which once becoming
impure must be destroyed (There is no way to re-purify them - see verse Lv11-33.)
Hence we conclude that the Torah went out of its way to salvage the nearly worthless
clay utensils of a slanderer.
Again, we emphasize that Rashi made his derivation through logic: The emphasis in the Non-Verse rule is on derivation thru logic,
spreadsheets or diagrams. In the example reviewed above, Rashi shows how the absence of step #3 would lead to loss
of money and hence the inclusion of step #3 must therefore be to save the petty cash
associated with clay utensils.