This verse contains three distinct pieces of information. The first is the number of the Nephite dead. Of course that number is so great that it was not counted, but that very fact gives us an indication of the greatness of the number. It is tempting to assume that this number was monstrously large, as later in the Book of Mormon we get counts of ten thousand, and forty four thousand (as in Mormon 2:9). While it might be tempting to push this unnumbered number higher than the highest count, we must remember that counts are used imprecisely in the Book of Mormon (see the discussion of counts and estimates following Alma 2:18 in this commentary).
It is very likely that the casualties were over a thousand, but we should understand that Mormon’s purpose is to stress the calamity of the war, not the specific numbers. The number might be unnumerable because it is too high to count, or because it is too painful to count. After the September 11, 2001 attack on the World Trade Center, New York Mayor Rudy Guiliani stated that the when the dead were counted, it would be “more than we can bear.” It is that sentiment that Mormon expresses here.
The second piece of information concerns the burial and burial rites for the fallen Nephites. Mormon includes two facets of this burial. First is the fact of the burial, and the second is the social effect of the burial. For the Nephites, it appears that the rites of burial were accompanied by certain rituals. All we know of them is that they included fasting, mourning, prayer, and multiple days. While we cannot know how much of the Old World culture remained in the New World Nephite burial customs, it is still instructive to have an insight into a comparison with those Old World traits:
“One marked feature of Oriental mourning is what may be called its studies publicity and the careful observance of the prescribed ceremonies. Genesis 23:2; Job 1:20; Job 2:12; 1. Among the particular forms observed the following may be mentioned: (a) Rending the clothes. Genesis 37:29, 34; Genesis 44:13; etc. (b) Dressing in sackcloth. Genesis 37:34; 2 Samuel 3:31; 2 Samuel 21:10; etc. (c) Ashes, dust or earth sprinkled on the person. 2 Samuel 13:19; 2 Samuel 15:32; etc. (d) Black or sad-colored garments. 2 Samuel 14:2; Jeremiah 8:21; etc. (e) Removal of ornaments or neglect of person. Deuteronomy 21:12, 13; etc. (f) Shaving the head, plucking out the hair of the head or beard. Leviticus 10:6; 2 Samuel 19:24; etc. (g) Laying bare some part of the body. Isaiah 20:2; Isaiah 47:2; etc. (h) Fasting or abstinence in meat and drink. 2 Samuel 1:12; 2 Samuel 3:35; 2 Samuel 12:16, 22; etc. (i) In the same direction may be mentioned diminution in offerings to God, and prohibition to partake of sacrificial food. Leviticus 7:20; Deuteronomy 26:14; (k) Covering the “upper lip,” i.e. the lower part of the face, and sometimes the head, in token of silence. Leviticus 13:45; 2 Samuel 15:30; 2 Samuel 19:4; (l) Cutting the flesh, Jeremiah 16:6, 7; Jeremiah 41:5; beating the body. Ezekiel 21:12; Jeremiah 31:19; (m) Employment of persons hired for the purpose of mourning. Ecclesiastes 12:5 Jeremiah 9:17; Amos 5:16; Matthew 9:23; (n) Akin to the foregoing usage the custom for friends or passers-by to join in the lamentations of bereaved or afflicted persons. Genesis 50:3; Judges 11:40; Job 2:11; Job 30:25; etc. (o) The sitting or lying posture in silence indicative of grief. Genesis 23:3; Judges 20:26; etc. (p) Mourning feast and cup of consolation. Jeremiah 16:7, 8;
2. The period of mourning varied. In the case of Jacob it was seventy days, Genesis 50:3; of Aaron, Numbers 20:29; and Moses, Deuteronomy 34:8 thirty. A further period of seven days in Jacob’s case. Genesis 50:10; Seven days for Saul, which may have been an abridged period in the time of national danger. 1 Samuel 31:13; With the practices above mentioned, Oriental and other customs, ancient and modern, in great measure agree.” (“Mourning.” Dictionary of the Bible, William Smith .)
The Nephite practices overlap those of the Old World in the fasting and prayer, and in the multiple days assigned to the mourning period. While we do not know whether or not there were specific visible signs of mourning, it would not be surprising if these were not also present among the Nephites. When Mormon lists mourning as one of the aspects of the period following the burial, we may assume that, for him, mourning included certain visible (and perhaps audible) traits.
The last piece of information in this verse is that “there began to be continual peace…” The phrase “continual peace” is characteristic of Mormon’s redaction, and is not found in the small plate material in the Book of Mormon. While the general meaning is obvious, the duration of “continual” changes dramatically. For instance, in Mosiah 19:29, Limhi has “continual peace” for only two years. In this verse we have continual peace assigned to the sixteenth year of the reign of the judges. In verse 5 we will see that the seventeeth year also gives us “continual peace.” We may therefore assume that this is a term that Mormon applies to year periods, and that it is used when there is a lack of armed battle, or of internal contention. Either of those two elements will disrupt the peace, and Mormon sees them as equally threatening. We have just ended the fifteenth year of the reign of the judges with a terrible war. There will then be two years of peace, and the next event that Mormon will list that disturbs that peace is the arrival of Korihor (verse 6). For Mormon, Korihor is a disruption of peace just as was a war.