Why was the Mormon religion made?

The Church of Jesus Christ of Latter-day Saints (commonly called the "Mormon" church) began due to a young boy's prayer. In 1820, Joseph Smith was 14 years old. He lived in an area of New York that was experiencing a huge religious revival. Some of his family had joined a Presbyterian Church, some were attending a Methodist Church, and his father had met a couple times with a Unitarian Church. Joseph wanted to join a church, but didn't know which one he should join.

After studying the Bible to find an answer, he came to James 1:5, which says that if anyone lacks wisdom, they should ask God. Joseph went to the woods near his home to pray - to ask God which church he should join. As he began praying, he saw "a pillar of light... which descended gradually until it fell upon [him]." In that light he "saw two Personages." One of these called him by name and said, "This is my Beloved Son. Hear Him." Joseph asked these personages which church he should join. God the Father and Jesus Christ answered him by saying that he should "join none of them, for they were all wrong" and was told that he would receive further instruction later.

Throughout the next decade, Joseph was visited and taught by angels and Biblical prophets, who restored to him the full and pure Gospel of Jesus Christ, as well as the authority to preach that Gospel. Moroni, a Book of Mormon prophet, showed him the place where ancient plates were buried. Joseph was able to translate these plates by the power of God, and they were published as the Book of Mormon. Following the publication of the Book of Mormon, the first official meeting of the Church of Jesus Christ of Latter-day Saints was held on April 6, 1830.

So, I suppose the short answer is because God the Father and Jesus Christ directed Joseph Smith to do so.

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