Lynn answered...

Some call Mormonism a cult because it is not a "traditional" Christian church. The primary complaint of the "traditionalists" (generally Protestant Churches) is that we do not believe in the doctrine of the trinity as it relates to the nature of the Godhead. The doctrine of the trinity was codified in the Nicene Creed in 325 AD, many years after the death of Christ and the Apostles. It basically says that the Godhead, The Father, Son and Holy Ghost, are one being in "substance." Since Mormonism does not accept this doctrine, they say we believe in a different Christ than they do and therefore are a cult. It is curious that this "trinitarian" doctrine is not taught anywhere in the Bible.

Mormons believe the Bible is the Word of God. The Bible (and the early church established by Jesus and His Apostles) teaches that the Godhead indeed consists of The Father, Son and Holy Ghost. But, it teaches that they are: 1) three distinct individuals as expressed in Acts 7:54-60 where Stephen is being stoned. "He being filled with the Holy Ghost looked up steadfastly into heaven and saw Jesus standing on the right hand of God." And it teaches 2) they are one in purpose, not in substance (John 17 where Jesus offers his intercessory prayer, particularly verses 20-23.) This is what Mormons believe.

It is noteworthy that the early Christians were called the "sect of the Nazarenes" (Acts 24:5) and were considered a cult by the Sadducees and Pharisees, the predominant religions of the day.