He's pointing out that heretical cults come into existence, and must not be conflated with the mainstream religion. Just as a Christian would say the writings of Joseph Smith or the Watchtower have nothing to do with Christianity, a Jew will say that the Essenes have nothing to do with Judaism.
His equivocating between Joseph Smith and the Essenes is absurd because of the separation by time, culture, language, history, and religion. Joseph Smith had nothing to do with the origins of the Essenes
Just because an idea is expressed in a new form, eg., from modern Christianity to Joseph Smith does not necessarily make it wrong. We throw around terms like “cult” and “heresy” as perjoratives, but have you forgotten that modern Christianity started out as a cult itself…arguably, from the sect of Judaism, namely, the Essenes? Eventually, the LDS will be considered a mainstream religion if it continues to grow. That is how it works.
Personally, I like to investigate what is common among religions because I think God is over all nations. Different religions take on different forms but there remains an underlying common thread. I touch on it in this OP with the Holy Spirit forming a moral conscience in man irregardless of race, nationality, language, and sex. Of course, other religions would call it by another name: Logos, Mind, Wisdom of God, Hermes, for example.
Every religion starts out as a cult until it grows big enough to become mainstream. Judaism likely took on aspects of the Zoroastrian religion during Babylonian/Persian rule. In fact, Noah’s flood comes from the Epic of Gilgamash written up to 1,000 years before in Babylonian lore. Therefore, In comparative religion a “cult” is defined as a branch off a mainstream religion before it becomes mainstream itself. Moreover, a “heresy” originally meant a new way of teaching something. People would go to hear a new heresy to learn something new.
