The Pains of Redemption

The Gemara in Sanhedrin (98b) describes the hardships know as the "birth pangs of Mashiach". Three amoraim - Ulla, Rabba, and R. Yochanan - were so frightened of these hardships that they prayed "Let [Mashiach] come, but may I not see him." Rav Yosef, however, disagreed. He says "Let him come, and may I merit to sit in the shadow of his donkey's dung!"

Rav Kook Zt"l explains in his famous letter to the Ridvaz (Igrot Raiya 555) that the three amoraim were not worried about the physical hardships but rather of the spiritual troubles that would befall the Jewish people on the eve of the coming of the Mashiach. He did not want to see so many Jews leave the path of the Torah and adopt heretical ideologies. As the Gemara describes in Sotah (49b) "Cutzpah will increase; a daughter will stand up to her mother and a daughter-in-law to her mother-in-law; the youth will insult the elderly; the kingdom will turn to heresy." To any Jew who is sensitive to the spiritual mission of Israel, this will be almost too much to bear.

Rav Yosef, however, as usual looks for the inner meaning in everything. The donkey symbolizes materialism (חמור - חומר), a departure from spiritual qualities. The dung represents sins, the waste-product of a materialistic outlook. Rav Kook points out that the "material", unclean/kosher donkey has a special inner holiness. It is the only unkosher animal whose firstborn is holy. It can be redeemed. Rav Yosef wanted to sit in the shade of the donkey's dung because he realized that where there is shade, there must be light.