[1] Archbishop Gennady of Novgorod had uncovered the Heresy of the Judaizers in 1487 and Zosimus's entire metropolitanate was overshadowed by this crisis.

Gennady wrote a letter in 1490 to Zosimus and other bishops in the Russian church demanding a council be convened and the heresy be dealt with.

The council convened less than a month after Zosimus' elevation to the metropolitan throne and condemned the heresy.

[2] Gennady demanded that the heretics be severely punished - hanged and burned - and not merely incarcerated, but Zosimus and Grand Prince Ivan III opposed these harsher methods.

Zosimus was eventually accused of being a secret heretic and, on 17 May 1494, he was removed from the metropolitan throne on charges of heresy and sodomy.