From time to time, the ongoing confusion over Moroni and Nephi arises. This is a brief explanatory note.
When originally published in the Times and Seasons in 1842, Joseph Smith's history said that it was Nephi who first appeared to him in 1823 to tell him about the plates.
He called me by name, and said unto me that he was a messenger sent from the presence of God to me, and that his name was Nephi. That God had a work for me to do, and that my name should be had for good and evil, among all nations, kindreds, and tongues; or that it should be both good and evil spoken of among all people.
Church historians later edited the history so that it now reads Moroni.
33. He called me by name, and said unto me that he was a messenger sent from the presence of God to me, and that his name was Moroni; that God had a work for me to do; and that my name should be had for good and evil among all nations, kindreds, and tongues, or that it should be both good and evil spoken of among all people.
This detail has led critics to claim that Joseph couldn't get his story straight, but there is a better explanation.
There's no doubt the 1842 publication in the Times and Seasons was an error. Joseph had identified the messenger as Moroni in the Elders' Journal in 1838. Oliver Cowdery had done the same in 1835.
How can we account for such an obvious error in the 1842 Times and Seasons?
First, the publication of the error is evidence that Joseph Smith, who was the named editor of the newspaper at the time, was merely the nominal editor (i.e., in name only). He didn't review the paper closely, if at all, prior to publication.
Second, the history published in the 1842 Times and Seasons was not written by, and probably not dictated by, Joseph Smith. Instead, it was compiled by his scribes beginning in 1838.
Of course, this raises the question, why would the scribes think it was Nephi who first visited Joseph and not Moroni?
The answer could be that they knew Joseph had multiple encounters with both Moroni and Nephi.
Brigham Young explained in a letter to his son that "There is really no discrepancy in the history about these names. It was Moroni who delivered the sacred records and Urim and Thummim to Joseph, but Nephi also visited him."
Those who have read the Saints book, volume 1, will remember the account of a divine messenger showing Mary Whitmer the plates in Fayette, NY. The book claims the messenger was Moroni. This is a revisionist historical narrative, designed to accommodate M2C by deflecting attention from David Whitmer's testimony that this same messenger took the Harmony plates (the abridged plates) to Cumorah before bringing the unabridged plates of Nephi to Fayette.
The claim that the messenger was Moroni also contradicts what Mary Whitmer herself reportedly said; i.e., that the messenger identified himself as Brother Nephi.
By changing the historical narrative to omit Nephi and insert Moroni into the account of the messenger who took the Harmony plates to Cumorah and showed the plates of Nephi to Mary Whitmer, our Church historians have compounded the confusion that long existed over the claim in the 1842 Times and Seasons that it was Nephi who first appeared to Joseph Smith.
As usual in questions about Church history, we are better off accepting the statements of those involved than the revisionist history of our modern historians.
The other problem with the Moroni narrative is the doctrinal problem of teaching that resurrected beings are shape shifters.
"The spirit and the body shall be reunited again in its perfect form." Alma 11:43
The Moroni/Nephi confusion is complicated by later references. To keep things straight, here's a helpful chronology.
1832. David Whitmer and Hyrum Smith, as missionary companions, teach and baptize the family of Zina Peterson, who later wrote about her experience. This is the last known connection between Zina and David.
1835. In Letter VI, Oliver Cowdery named the angel who visited Joseph in 1823 as Moroni.
I believe that the angel Moroni, whose words I have been rehearsing, w[h]o communicated the knowledge of the record of the Nephites, in this age, saw also, before he hid up the same unto the Lord, great and marvelous things, which were to transpire when the same should come forth
1838. Joseph identified the angel as Moroni in Elders' Journal, July 1838, 42-43.
Question 4th. How, and where did you obtain the book of Mormon?
Answer. Moroni, the person who deposited the plates, from whence the book of Mormon was translated, in a hill in Manchester, Ontario County New York, being dead, and raised again therefrom, appeared unto me, and told me where they were; and gave me directions how to obtain them. I obtained them, and the Urim and Thummim with them; by the means of which, I translated the plates; and thus came the book of Mormon.
1838. Joseph Smith's History is compiled by his scribes.
1842. Joseph Smith's History is serialized in the Times and Seasons. The 15 April edition says it was Nephi who visited Joseph Smith. Later, Church historians changed this to Moroni when they prepared the version for the Pearl of Great Price.
1877. Joseph F. Smith and Orson Pratt visit David Whitmer, who relates the account of meeting a divine messenger on the road from Harmony to Fayette.
1877. Edward Stevenson explained why he asked David about the angel.
"I wish to mention an Item of conversation with David Whitmer in regard to Seeing one of the Nephites, Zina Young, Desired me to ask about it. David Said, Oliver, & The Prophet, & I were riding in a wagon, & an aged man about 5 feet 10, heavey Set & on his back, an old fashioned Armey knapsack Straped over his Shoulders & Something Square in it, & he walked alongside of the Wagon & Wiped the Sweat off his face, Smileing very Pleasant David asked him to ride and he replied I am going across to the hill Cumorah. Soon after they Passed they felt Strangeley and Stoped, but could see nothing of him all around was clean and they asked the Lord about it. He Said that the Prophet Looked as White as a Sheet & Said that it was one of the Nephites & that he had the plates."
1878. In a letter dated 7 Jan 1878, Edward Stevenson writes to John Taylor about his visit to David writing "he related many very interesting items of seeing one of the Nephites in company of the Prophet and Oliver when Joseph's countenance became almost transparent &c."
1888. Andrew Jensen reports an account of from a grandson of Mary Whitmer about her seeing the plates. Jensen inserts a parenthetical that Mary was wrong because the messenger must have been Moroni.
"I have heard my grandmother (Mary M. Whitmer) say on several occasions that she was shown the plates of the Book of Mormon by an holy angel, whom she always called Brother Nephi. (She undoubtedly refers to Moroni, the angel who had the plates in charge.)"
Andrew Jensen's speculation (possibly attributable to the grandson) appears to be where the narrative was changed.
1891. Stevenson writes a letter to Wilford Woodruff dated Oct. 6, 1891, in which he relates:
David also related that while coming from Harmony Pa.. - about halfway to Fayett, [sic] N.Y., - which was June 1829 - they saw Maroni [sic] who at that time appeared as an ordinary man and common attire with a knapsac on his back. he asked him to ride with them, but he replied I am only going over to Cumorah. Steped back and disappeared. Oliver and David asked the Prophet to enquire of hte Lord who this misterious and distinguished visitor was. David told me that when he looked back at the prophet he looked to him nearly transparent and said that was <Maroni> with the plates, &c. - soon after their arrival at Fayett, David said his mother saw Maroni and he also opened the plates turning them over leaf by leaf- but there was some portion sealed with 3 gold rings...
The Brethren in Alberta are feeling well, and are much more united in their faith, without so much distinction and classification, as we have in our Babylonish Pride and Classification of S.L.C. and other older settlements, which proved a curse to both the Jaredites as well as the overthrow of the Nephites..... since I have been here by request I have given 6 public Lectures in Alberta on the subject of the early rise of the Church and the coming forth of the Book of Mormon Illustrated by 3 paintings one of the Hill Cumorah 2d Joseph the Prophet, and the Angle Maroni delivering the previous Record and the 3d one with the 7 lines of Characters coppied from the plates by the Prophet, and sent to Professor Anthon N.Y. by Martin Harris.
In 1911, the Improvement Era published an account of Nephi visiting the Indians in Utah.
Messenger to the Indians
The following comes addressed to President Joseph F. Smith: "In the summer of 1876, a personage appeared to the Indians out west of St. George at a place called Duck Creek. This personage told the Indians that he was one of their forefathers and had many things to tell them, as he had lived a long time upon the earth.
By this man's request, runners were sent out to all the nearby bands of Indians to bring them together. "This personage, whom the Indians described as having a long white beard, and as being dressed in white, remained with them for several months, and during all that time not an Indian was seen along the Virgin river or its tributaries.
"When the Indians returned to their homes, my brother Nephi Johnson and myself Sextus E. Johnson called the Indians together and questioned them about the personage who had appeared to them out west. "They told us that his name was Nephi, the same as my brother Nephi. He told them that the 'Mormons' were their friends and they must listen to their counsels, and that in time prophets would come among them and lead them to live a better life.
"They asked him how long he had lived upon the earth. He told them, but it was so many moons that they could not enumerate them, but it was many hundred years, in fact far beyond their comprehension.
"President Joseph F. Smith: We are satisfied that this personage spoken of did appear to the Indians out west, and that his name was Nephi, one of the apostles of the Savior whom He chose during his sojourn upon this land.
Nephi and S. E. Johnson. "Written from memory by S. E. Johnson at Colonia Morelos, Sonora, Mexico - September 11, 1911" -- Nephi and S. E. Johnson, “Messenger to the Indians,” Improvement Era, November, 1911, 15:79-80
Here's a link to the original version in the Improvement Era:
An earlier original record of this is on the Church history website, but it is "closed to research."