The word cult is one of the more “loaded” words in the English language. The connotations in today’s common usage is entirely bad, if not outright evil. The word religion has a fairly well-recognized definition, but the meaning of the word cult varies quite broadly. If you look up the first definition in the dictionary, you will find that true, original, primitive Christianity was a cult by that definition. In fact, the Jesus movement was called a Greek word which is more or less equivalent to the word cult. They were called “The Way” (Acts 19:9, 22:4, etc.),which, in context is essentially calling the Church a cult. The Church was also called a sect (Acts 24:14, Acts 28:22). Again, the word cult could have been used rather than sect in the translation of these two verses.
Let me give you a mainstream dictionary definition of a cult: “a system of religious veneration and devotion directed toward a particular figure or object.” Surely the early church, led by the apostles, fit this definition. Here is a second definition, a bit closer to the strongly negative connotation in our society: “a relatively small group of people having religious beliefs or practices regarded by others as strange or sinister.” Again, you can see that the first century church definitely would have been considered a cult by outsiders. I found a third definition which is probably even closer to the negative connotation of most English-speakers: “a misplaced or excessive admiration for a particular person or thing.” Again, depending on your definition of the words”misplaced” and “excessive,” this would also apply to the early church.
Let me do this. Let me give what I think is actually the most common definition of the world cult in its normal usage here in the US. A cult is a small group of believers who give excessive devotion and obedience to a single living (or possibly recently dead) person, to include giving up most or all possessions to the leader and the right to make decisions for themselves. If this is the definition of a cult, then Christianity was never a cult, but I think that outsiders may have falsely labeled the true Christian church of the first century using the term I just defined. Jesus did not demand that all members of his church turn in all their funds, although a sub-group more or less did that. Jesus did not demand that people fully give up their autonomy, but he did demand a very high level of commitment to himself.
In summary, a cult is a kind of a religion. In other words all cults are religions, but most religions are not cults. However the word itself has a really broad range of meaning. In the common usage of the word cult in the United States the meaning is entirely negative, and perhaps for good reason. We need a word for this bad thing. However, the true Christian Church that Jesus died to establish has many of the qualities of a cult, depending on the definition of the word being used. If I were in an open conversation with more or less random people, I would not say that the true church is a cult. That would surely be misunderstood and used to the disadvantage of genuine Christianity. However, in a controlled situation in which I could define terms, I would say that the primitive church we find in Acts was a cult. It also, therefore, obviously, was a religion as well..