According to Bruce Warren, we can approximate the date of the appearance of the Messiah to the Nephites. Although we are told that the destruction signifying His death began on the fourth day of the thirty-fourth year and only lasted for three days, 3 Nephi 10:18-19 indicates that it was not until "the ending of the thirty and fourth year" that Christ "did truly manifest himself unto them." His appearance to the Nephites was apparently almost a full year after the great destruction.
3 Nephi 11:1-8 states that "a great multitude gathered together, of the people of Nephi, round about the temple which was in the land Bountiful . . . and behold, they saw a Man descending out of heaven." The account that follows is of Christ's visit and teachings among the Nephites. From the Book of Mormon, the information we have to work with is as follows:
(1) The Savior's appearance was in the ending of the thirty-fourth year of the Nephite calendar--Table 1 shows that the first day of the Nephite thirty-fifth year would have been March 29, A.D. 34 on our Gregorian calendar, so the ending of the thirty-fourth year would almost certainly have been in A.D. 34 as well. That gives us the year of His appearance: A.D. 34.
(2) The Nephites were gathered in a great multitude at the temple in the land of Bountiful. Regarding the purpose of their gathering, it is perhaps instructive to note that the week of the Passover for A.D. 34 would have been from Tuesday, March 21 (the 15th of Nisan) to Monday, March 27 (the 21st of Nisan).
The fact that the Nephites were still following the Mosaic Law at the time of Christ's appearance would explain what they were doing at the temple in Bountiful. Given that the dates for the Passover celebration would have fallen, according to the Book of Mormon description, "in the ending of the thirty and fourth year" (or more specifically as shown on the bottom half of Table 2, in the last week of the thirty-fourth year), they were very likely gathered for the week of the Passover feast.
Considering the message that the Savior was bringing to the Nephties, Passover would certainly have been a timely opportunity for His visit. This message was actually given in part during the third day of darkness at the beginning of the year when He declared, "by me redemption cometh, and in me is the law of Moses fulfilled" (3 Nephi 9:17).
If even after this the Nephties were still gathered to observe Passover at the end of the year, then they had not understood what the savior had told them. In fact, among the first things He teaches them after His arrival is a variation of this first statement. At the end of chapter 12 he says, "those things which were of old time, which were under the law, in me are all fulfilled. Old things are done away, and all things have become new" (3 Nephi 12:46-47).
Even this was apparently not enough explanation for some of the more tradition-bound Nephites, for 3 Nephi 15:2 reveals that "there were some among them who marveled, and wondered what he would concerning the law of Moses; for they understood not the saying that old things had passed away, and that all things had become new."
In response, the Savior repeats several times, "the law is fulfilled that was given unto Moses. Behold, I am he that gave the law; therefore it hath an end. . . . the law which was given unto Moses hath an end in me" (3 Nephi 15:4-8).
What more effective context than that of Passover could the Lord have used to officially notify the Nephties about the end of the Mosaic Law and inaugurate the Law of the Gospel? [Bruce W. Warren, "1 Ben 6 Mak: Part Two," in Jace Willard ed. The Book of Mormon Archaeological Digest, Volume II, Issue III. Orem: Book of Mormon Tours, 1999, pp. 4-5]