***DISCLAIMER*** The following is far from an exhaustive post. Instead, it simply makes a best effort to answer the question.
In considering this question, we must first define what a “cult” is.
The word “cult” is actually found in Scripture in the NASB translation (Deuteronomy 23:17; 1 Kings 14:24, 15:12; 2 Kings 23:7; Job 36:14). However, it is not used in the same way the word is used to describe certain religions (i.e., Mormons, Jehovah Witnesses, etc.). Therefore, we must consider secondary sources in defining what a cult is.
The late Dr. Walter Martin, in his book Kingdom of the Cults, states that a cult is “defined as a group of people gathered about a specific person or person’s misinterpretation of the Bible” (p. 17). For example, as Martin notes, Jehovah’s Witnesses primarily follow the interpretations of Charles T. Russell and J.F. Rutherford, Christian Scientists follow the interpretations of Mary Baker Eddy, and Mormons, “by their own admission, adhere to those interpretations found in the writings of Joseph Smith and Brigham Young” (pp. 17-18). Ron Carlson & Ed Decker, in their book Fast Facts on False Teachings, describe four different types of cults (p. 137). These include Pseudo-Christian cults (those that end up denying the “central doctrines of historic, orthodox, biblical Christianity” via their particular revelation or teaching), Oriental cults (those “that have their basis in Oriental or Eastern philosophy, specifically Hinduism and Buddhism”), New Age cults (a combination of Western Secular Humanism, Eastern Hindu Mysticism and the occult) and Spiritist cults (which “spans the whole universe of darkness, including astrology, tarot cards, palmistry, numerology, witchcraft, Satanism, séances, clairvoyance and channeling”; pp. 137-141).
Martin’s definition of a cult described groups with either one or more person’s “misinterpretation of the Bible.” It would be good to know what represents the right way to interpret the Bible. In his DVD Herman Who?, Todd Friel explains how the grammatical historical method of interpretation best determines “exactly what the author intended and how the original audience would have understood it.” This would indeed be the best way because if one interprets the Bible based on how he/she understands it instead of what the author tried to say, then one can easily make the Bible the most abused, misinterpreted book in the world.
With a brief understanding of both what a cult is and what represents the best way to interpret the Bible, one can now compare the core doctrines of Eastern Lightning to Scripture to see if its doctrines are in agreement with Scripture. If it is not in agreement, then one can determine whether or not it is a cult based on the aforementioned definition of what a cult is.
According to an article by christianapologeticsalliance.com, Eastern Lightning began in about 1990. Zhao Weishan represents its founder. According to him, “Almighty God has come in the form of a Chinese woman and bases that claim on what Jesus said” in Matthew 24:27. The verse reads as follows:
“For just as the lightning comes from the east and flashes even to the west, so will the coming of the Son of Man be.”
Nowhere in that verse is a Chinese woman even mentioned. Furthermore, nowhere in Scripture is a Chinese woman verbatim even discussed. This is a clear case of eisegesis, or reading into the biblical text something that is not there. As a result, a misinterpretation of the Bible exists. Therefore, Eastern Lightning represents at least one characteristic of a cult.
Another thing to consider is Eastern Lightning’s teachings. One can find information on this organization via the website holyspiritspeaks.org. Under its “Books” section, one will not find a Bible anywhere. Instead, it has much literature that presumably represents extrabiblical revelation. For example, one will find under part one of The Word Appears In The Flesh many supposed utterances from God. However, these have no biblical citation. Furthermore (at least in the case of the first two utterances), these are dated in the early 90’s. This would be in agreement with Carlson & Decker’s definition of a Pseudo-Christian cult. It is clear that Eastern Lighting has a fixation on extrabiblical revelation. However, this extrabiblical revelation is not a good thing because it adds to God’s Word (Revelation 22:18-19; Deuteronomy 4:2; Proverbs 30:6). Given, at the very least, Eastern Lightning’s emphasis on extrabiblical revelation (which adds to God’s Word) and the aforementioned misinterpretation of Matthew 24:27 by Eastern Lightning’s founder (in this case a twisting of God’s Word), it is safe to say that Eastern Lightning is a cult.