This small book of prayers, though rather modest in appearance, in fact testifies to one of the most curious events in Jewish history. In 1665, an Ottoman Jew by the name of Shabbetai Zvi proclaimed himself Messiah, and from Istanbul to Amsterdam Jewish communities were swept up in messianic fervor of unprecedented proportions. Just how fervent the feelings grew can be gauged from the frontispiece of this prayer book, which shows Shabbetai Zvi in all the royal panoply due a Messiah and king of Israel, down to the worshipful disciples and Lions of Judah to guard his throne. But the fervor was short-lived. On September 15, 1666, the Jewish world was stunned by the news that Shabbetai Zvi, summoned before the Ottoman Sultan, chose Islam over death. The inevitable reaction set in, with the result that momentos to Shabbatean fervor, such as this prayer-book, are today exceedingly rare.