Jewish History: Biblical History: The Weeping of Jacob and Esau:
When Jacob and Esau embraced, why did they both weep?
The Midrash Rabbah says, in the name of R. Yanai, that when Esau
embraced Jacob, he tried to bite Jacob's neck rather than to kiss him
(le-nashcho rather than le-nashko), but Jacob's neck became very hard,
and Esau's teeth were blunted. They therefore both wept, one because
his neck hurt and the other because his teeth hurt. The Targum Yonason
also gives this explanation about why they both wept.
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