Coming to terms with Protestantism

Professor Tark Ji-il, a religion professor at Busan Presbyterian University, said the Book of Mormon, which Mormons believe is an additional testament of Jesus Christ, is what sets Mormons apart from mainstream Christians.
The Book of Mormon is a religious text which Joseph Smith, the founder of the church, claimed to have translated from ancient plates containing a history of early inhabitants of the Americas that were compiled by a prophet called Mormon. Mormons give the book equal authority with the Bible.
One of the dilemas for mainstream Christians, Mr. Tark said, is that while they do not recognize the foundations of the Mormon faith, they are forced to recognize that Mormons lead a disciplined way of life. Mormons also have the highest birth rate and lowest divorce rate of all religious groups in the United States, where it is the fourth largest congregation, he said.
Mr. Tark said the Mormon church grew out of the religious disputes taking place in New England region of the United States in the early 1800s. Joseph Smith said God revealed to him that all other Protestant churches were invalid and instructed him to start a new one.
One of the biggest negative perceptions about Mormons is that they engage in polygamy, but the church discontinued that in 1896 and polygamists were expelled.