While most Christians believe that angels are an entirely separate type of being than humans are, members of the Church of Jesus Christ of Latter-day Saints (abbreviated as the "LDS church" but popularly known as the "Mormon church") believe that angels are people in different types of spiritual progression -- from people who haven’t yet lived on Earth but will in the future, to people who have already completed their earthly lives and now live in heaven.
Mormons also believe that the angels in heaven may either exist in spiritual form or with physical bodies of flesh and bone. When they appear on Earth, Mormons believe, angels may often look just like human beings.
The Book of Mormon, the most important sacred LDS scripture besides the Bible, was sent by God to people through an angelic messenger, Mormons believe. That messenger -- the angel Moroni -- was once a human prophet who lived in ancient America but who became an angel after death and appeared to another prophet many years later to help start the LDS church.
Mormons believe that Moroni appeared to a prophet named Joseph Smith between 1823 and 1827 to tell him about some golden plates hidden inside a hill near Smith’s home in Palmyra, New York. On the plates, Moroni said, Smith would find written scriptures describing the history of ancient Christianity in America.
Moroni said that he had once been a human being, and that during his life on Earth, he had worked with his father Mormon to write the information on the golden plates. In the year 421 AD, Moroni said, he buried the plates inside a hill called Cumorah so they would be would be persevered for future generations.
Smith said that he translated the ancient language on the plates into English with help from Moroni, and later encountered visions of John the Baptist and the apostles Peter, James, and John, whom he said all appeared in angelic form and gave him spiritual authority to start the new church. In 1830, Smith published his translation as the Book of Mormon.
The holy angels in heaven love God and express that love by praising him, the Book of Mormon says.
Alma 36:22 describes a prophet’s vision of angels praising God: "... God sitting upon his throne, surrounded with numberless concourses of angels, in the attitude of singing and praising their God; yea, and my soul did long to be there."
Working for Jesus Christ
All holy angels serve Jesus Christ, doing their best to spread his Gospel message and help carry out his plan to redeem the fallen world of Earth, says the Book of Mormon.
Moroni 7:22 says that in ancient days, God sent angels to prepare people for Jesus Christ coming to Earth: "For behold, God knowing all things, being from everlasting to everlasting, behold, he sent angels to minister unto the children of men, to make manifest concerning the coming of Christ; and in Christ there should come every good thing."
Now, Moroni says in 7:30-32, angels continue to work for Jesus: "For behold, they are subject unto him, to minister according to the word of his command, showing themselves unto them of strong faith and a firm mind in every form of godliness And the office of their ministry is to call men unto repentance, and to fulfill and to do the work of the covenants of the Father, which he hath made unto the children of men, to prepare the way among the children of men, by declaring the word of Christ unto the chosen vessels of the Lord, that they may bear testimony of him. And by so doing, the Lord God prepareth the way that the residue of men may have faith in Christ, that the Holy Ghost may have place in their hearts, according to the power thereof; and after this manner bringeth to pass the Father, the covenants which he hath made unto the children of men."
Delivering Messages to People
When angels appear to people, they’re often delivering important messages from God, the Book of Mormon says.
An angel got the attention of a man named Alma who was rebelling against God and warned him to stop persecuting Christians, the Book of Mormon records in Mosiah 27:11-16. Verse 11 describes the impressive scene when the angel appears: "... he descended as it were in a cloud; and he spake as it were with a voice of thunder, which caused the earth to shake upon which they stood.”
The angel informs Alma that God sent him to deliver a message in response to Alma’s father’s prayers for Alma: "... for he has prayed with much faith concerning thee that thou mightest be brought to the knowledge of the truth; therefore, for this purpose have I come to convince thee of the power and authority of God, that the prayers of his servants might be answered according to their faith. And now behold, can ye dispute the power of God? For behold, doth not my voice shake the earth? And can ye not also behold me before you? And I am sent from God." (verses 14 and 15). The angel then urges Alma in verse 16: "seek to destroy the church no more."
Like the Bible, the Book of Mormon also describes some fallen angels who rebelled against God and now work under the command of Satan, a demon who was once the angel Lucifer. Those angels, whom God had created for good, now tragically can only accomplish evil because they’re separated from God.
2 Nephi 9:9 describes the fallen angels: "And our spirits must have become like unto him, and we become devils, angels to a devil, to be shut out from the presence of our God, and to remain with the father of lies, in misery, like unto himself; yea, to that being who beguiled our first parents, who transformeth himself nigh unto an angel of light, and stirreth up the children of men unto secret combinations of murder and all manner of secret works of darkness."