Jewish Festivals in the Book of Mormon
While the Old Testament frequently mentions Jewish festivals, none of them are mentioned in the Book of Mormon, despite the fact that the book claims to be the history of an Israelite group.
Though none of the Old Testament festivals are mentioned by name in the Book of Mormon, there is much evidence of their practice that has been published. Perhaps it is too much to expect that the Book of Mormon should name them all. Most of the Old Testament references to the festivals are found in the law of Moses (Exodus through Deuteronomy), where they are instituted. One cannot compare this legal code with the Book of Mormon, which is mostly prophecy, preaching, and history. It would be more reasonable to compare Mormon’s abridgment with the main history of the Israelites, found in Joshua through 2 Kings. Most Bible scholars agree that the books of Joshua, Judges, 1-2 Samuel and 1-2 Kings were compiled or redacted at the same time and comprised the essential history of ancient Israel from the time of the conquest of the promised land down to the exile therefrom. (For example, note the similar phraseology found in Judges 3:7; 6:25-30; 1 Kings 14:15-16, 22-23; 16:31-33; 2 Kings 13:6; 17:10-12, 16; 21:3.) In this sense, it is roughly parallel in nature, though not in time, with the Nephite record.
Most biblical references to the two festivals of Passover and unleavened bread are found in the law of Moses. But in the main history portion of the Old Testament (Joshua through 2 Kings), there are only two references to them. Joshua and the Israelites celebrated the two feasts after crossing the Jordan river into the land of Canaan (Joshua 5:10-11). It is likely that this was the first time they had celebrated the feasts since the exodus. Joshua 5:2-9 expressly states that, prior to the celebration, they circumcised all Israelite males for the first time since leaving Egypt. (In Exodus 12:43-48, we read that uncircumcised males cannot participate in the Passover feast.) Later, we read that when a copy of the law (Deuteronomy according to most Bible scholars) was inadvertently discovered in the time of king Josiah, he and his people celebrated the Passover with unleavened bread (2 Kings 23:9, 21-23; 2 Chronicles 35:1, 6-9, 11, 13, 16-19). In both cases, we are dealing with the reinstitution of the festival, not an annual observance. The chroniclers later credited king Hezekiah with a similar celebration (2 Chronicles 30:1-2, 5, 15, 18, 21), but this may have been an attempt to build up Hezekiah, who was highly revered in post-exilic times. In this case, too, we are dealing with a reinstitution of the festival, of which, we are informed, there had not been “the like in Jerusalem” “since the time of Solomon” (2 Chronicles 30:26).
In the historical text of Joshua through 2 Kings, there is no mention of the feast of Tabernacles or of booths. Indeed, when it was reinstituted in the days of Ezra, it was noted that the feast had not been celebrated “since the days of Jeshua [Joshua]” (Nehemiah 8:17). The only reference to circumcision in Joshua through 2 Kings is the one performed in conjunction with the celebration in Joshua 5, noted above. Almost all the other references to circumcision are in the Pentateuch (Genesis through Deuteronomy).
The fact that circumcision is mentioned in Moroni 8:8 shows that Joseph Smith, if he authored the Book of Mormon, was aware that it should have been a normal practice among an ancient Israelite group. Why, then, would he avoid mentioning it earlier in the Book of Mormon? My answer is that he did not author the Book of Mormon and that its true authors, like the author(s) of Joshua-2 Kings, accepted circumcision as a given and saw no need to explain it. As for the complaint that the only other references to circumcision in the Book of Mormon are to circumcision of the heart, we should point out that this concept began with Moses (Deuteronomy 10:16; 30:6) and was repeated by Jeremiah (Jeremiah 4:4), a contemporary of Lehi.
I believe that the Nephites, like the ancient Israelites, accepted the festivals, the sabbaths, and other ceremonial aspects of the law of Moses as a given and therefore found no need to mention them at every turn in the road. That they did, indeed, practice unnamed ceremonies is confirmed in Mosiah 19:24, where we read, “And it came to pass that after they had ended the ceremony, that they returned to the land of Nephi.” The fact that “the ceremony” is mentioned only in passing and is not described suggests that it was such a normal thing that there was no need to explain it. I believe that these Nephites, who had just slain their king and perhaps others in battle, underwent the purification required under the law of Moses for those who had touched dead bodies.
 See John A. Tvedtnes, “The Nephite Feast of Tabernacles,” in John W. Welch (ed.), Tinkling Cymbals: Essays in Honor of Hugh Nibley (privately published by John W.Welch, 1978), and “King Benjamin and the Feast of Tabernacles,” in John M. Lundquist & Stephen D. Ricks (eds.), By Study and Also by Faith, Essays in Honor of Hugh Nibley, Vol. 2 (Salt Lake City: Deseret Book & FARMS, 1990. See also several of the articles published in Stephen D. Ricks and John W. Welch, King Benjamin’s Speech: “That Ye May Learn Wisdom” (Provo: FARMS, 1998).
 1-2 Chronicles are a later rewriting of the books of Samuel and Kings, which they contradict at many points. Prepared by priests and designed to reflect post-exilic Judaism, the Chronicles, while useful and sometimes incorporating materials from other sources, are not as reliable as the earlier records. Since the Chronicles reflect Jewish beliefs that postdate Lehi’s departure from Jerusalem, they are, along with the New Testament, less instructive about how the Nephites would have seen the festivals. The books of Chronicles in our Bibles are not the ancient “chronicles of the kings” of Judah and Israel sometimes referred to in 1-2 Kings as a source of additional information. Of interest to Latter-day Saints is the fact that the books of Samuel and Kings (which are termed 1-4 Kings in the Septuagint) are evidently abridgements of earlier contemporary annals of the kings. In this respect, they are a precedent for the two sets of records kept by Nephi (one a shorter version with emphasis on spiritual matters) and the abridgment prepared by Mormon.
 Later Jewish tradition makes Hezekiah a prime candidate for the Messiahship.
 For a discussion, see “The Nephite Purification Ceremony, chapter 24 in John A. Tvedtnes, The Most Correct Book: Insights From a Book of Mormon Scholar (Salt Lake City: Cornerstone, 1999, later reissued by Horizon).