Here the printer’s manuscript reads shall rather than the shalt that is expected when the subject is thou. The 1830 typesetter emended the shall to shalt. Although the vast majority of instances of “thou shalt” in the text have shown no tendency to replace shalt with shall (92 of them), there are 12 cases where such a change has occurred; most instances are restricted to a single edition (9 times) or to a momentary manuscript error (3 times, each marked below with an asterisk):
In three cases, however, the earliest textual source, the printer’s manuscript, reads “thou shall”; all of these have been edited in the printed editions to the standard “thou shalt”. Besides the case in Mosiah 12:11, we have these two examples:
One could argue that these three manuscript occurrences of “thou shall” are errors for “thou shalt”, especially given the three instances (in Alma 30:47, 3 Nephi 12:33, and 3 Nephi 13:5) where Oliver Cowdery initially wrote “thou shall” in the manuscript but then virtually immediately corrected the shall to shalt.
There are, however, two arguments that could be made in support of an original “thou shall” in the Book of Mormon text. First, there are numerous instances in Early Modern English where “thou shall” occurs instead of the historically correct “thou shalt”. For instance, in the online Oxford English Dictionary there are 24 occurrences of thou shall, in comparison to about a thousand occurrences of thou shalt; that is, over two percent of the cases in the OED read thou shall rather than the standard thou shalt. The King James Bible has no instances of thou shall, but interestingly the Wycliffe 1388 New Testament consistently has thou shall, as in the following examples from the Sermon on the Mount (spelling regularized):
For these examples, see pages 11–12 of The Wycliffe New Testament (1388), edited by W. R. Cooper (London: The British Library, 2002). It should be pointed out, however, that the Wycliffe translation generally uses third person singular verb forms with thou, such as thou has and thou does.
A second argument in favor of “thou shall” in the original Book of Mormon text is that there are examples in the earliest textual sources of other verbs for which the subject thou takes the base form of the verb rather than the historical -est ending:
(The example in 1 Nephi 14:8 is a yes-no question, not a command.) The instance in Mosiah 26:11 is like Mosiah 12:11 in that it involves a modal verb, may. Accepting these examples implies that we should also accept the occasional occurrence of “thou shall” whenever it is supported by the earliest textual sources. (For additional discussion, see under 1 Nephi 14:8.) Admittedly, the few examples of “thou shall” may be due to scribal error in the early transmission of the text. But because “thou shall” is possible, the critical text will accept “thou shall” in Mosiah 12:11, Mosiah 26:20, and Alma 10:7.
The textual history is similar for “thou wilt”: the vast majority of examples show no variation at all, but there are cases where the “thou wilt” has tended to be replaced by “thou will”. And there are two examples where the earliest reading has “thou will”. For discussion, see under Alma 8:20 and Alma 22:16. Also see under infl al endings in volume 3 for additional discussion.
Summary: Restore in Mosiah 12:11 the reading of the printer’s manuscript, “and again he saith that thou shall be as a stalk”; although “thou shalt” is the standard form, thou occasionally takes the base form of the verb in the earliest Book of Mormon text, as also in Early Modern English; two other cases of original “thou shall” are found in Mosiah 26:20 and Alma 10:7.