Toldot: The Accusation of Scorners

Hirhurim posts on Mockery and Accusations:

"The commentators ask why Rashi uses the term "leitzanei ha-dor" -- why refer to the mockers and not the wicked? Certainly falsely accusing a woman of adultery is a wicked thing to do (cf. Pardes Yosef; Beis Ha-Levi). The Gemara (Sotah 42a) lists four groups of people who do not receive the divine presence: the groups of mockers (leitzim), flatterers (chaneifim), liars (shakranim) and slanderers (mesaprei lashon ha-ra). Why does Rashi choose mockers and not slanderers? Presumably, slander is a more appropriate term for this offense."

But read it all for an elaboration and answer. The answer is better than the question, and I think deliberately so, as the purpose is to get to the diyuk of the conclusion, which is quasi-homiletical.

Rashi writes:

Abraham begot Isaac (Only after the Holy One, blessed be He, named him Abraham, did he beget Isaac. Another explanation:) Since Scripture wrote: “Isaac the son of Abraham,” it had to say: “Abraham begot Isaac,” because the scorners of the generation were saying that Sarah had conceived from Abimelech, for she had lived with Abraham for many years and had not conceived from him. What did the Holy One, blessed be He, do? He shaped the features of Isaac’s face to resemble Abraham’s, and everyone attested that Abraham had begotten Isaac. This is the meaning of what is written here: “Isaac, the son of Abraham,” because here is proof that “Abraham begot Isaac.” - [From Midrash Tanchuma, Toledoth 1]

It is a strange question, I think. Firstly, Rashi said leitzanim because that is what Tanchuma said. So the question is on the midrash, not on Rashi.

But it is obvious why leitzanim, jokers and scorners, is used. Could you imagine today, were such a thing to happen? If not for the Writer's Strike, it would be fodder for Jay Leno and for David Letterman. The point was not to make an accusation of adultery, but to knock down a miracle and to make funny insinuations about parentage. Of course it is leitznut! It might be rishut as well, but leitzanut is the most accurate depiction of the content and motivation.