Is Mormonism a Cult?

The secular media usually defines a cult as a group whose followers are denied basic freedoms by their leadership. Mormonism is not a cult according to this definition.

But evangelical Christians have typically defined a cult as a group that does not believe the essential Biblical doctrines. And a cult which mixes biblical truths with biblical contradictions (i.e. lies) is often called a “Christian cult.” 

During the 2012 Presidential election when Romney (a Mormon) was a candidate, some Christians backed away from calling the LDS Church a “Christian cult,” not wanting to create a divide between Mormonism and Biblical Christianity. And more recently, Dallas Jenkins, creator of The Chosen miniseries, has made public statements claiming that the Mormons he's working with worship the same Jesus as Christians. For Jenkin's specific quotes, see Using Discernment When Watching the Chosen, the section titled “In Brotherhood with Mormons.”

I'm not sure why Christians are so willing to defend Mormonism because Joseph Smith, the founder of the Mormon Church, claimed God told him that all churches except the LDS church were “of the devil,” “their creeds were an abomination” and those who professed faith in these churches were “corrupt.”(1)

One of many modern examples:

I recently came across a popular Mormon blog written by an female LDS theologian (and former LDS seminary professor). Her blog encouraged Mormon mothers to teach their children that the view of the Trinity accepted by all Catholic and Protestant denominations is in error. She confirmed Smith's teaching that “after the Apostles had all been killed, the Church as an organization remained, but the Gospel of Christ – including the Priesthood Authority – was no longer part of that Church.”(2)

She explained that when Christians accepted their “wrong” view of God, it was “a good day for the Devil and his associates.” And she claimed that only Mormons can understand what it means to be made in the image of God and call God their Father. 

Her statements accurately transmit the doctrine of the LDS church.

A kind Mormon friend explained to me that Mormons no longer use such harsh words as those Smith used, wanting to focus on our similarities, not our differences. But our differences are more significant than our similarities. And when the LDS beliefs are transmitted accurately, they harshly and arrogantly condemn Christianity.

We should treat Mormons with kindness, but we shouldn't mislead ourselves or others by ignoring our important doctrinal differences. Instead of seeking to accept or legitimize their beliefs, we should be seeking to share the true gospel with them. 
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(1)This is from official LDS Documents: Joseph Smith, History of the Church, vol. 1, p. 5-6 and Teachings of the Prophet Joseph Smith, compiled by Joseph Fielding Smith, p. 270. 
(2) Source

Other Resources:  
What is a Religious Cult by Hank Hanegraaff
Quick Comparison of Mormonism and Christianity by Matt Slick
Archive of 1-minute devotions on Mormonism