Sabbatai Zevi
The Emden-Eybeschutz controversy arose concerning the amulets which Emden suspected Eybeschutz of issuing. It was alleged that these amulets recognized the messianic claims of Sabbatai Zevi. Emden then accused Eybeschutz of heresy. Emden was known for his attacks directed against the adherents, or those he supposed to be adherents, of Sabbatai Zevi. In Emden's eyes, Eybeschutz was a convicted Sabbatean. The controversy lasted several years, continuing even after Eybeschutz's death.