The 1840 edition dropped the repeated shall in this passage, probably accidentally. There are many examples in the text of the repeated shall in conjoined predicates, and there has been no systematic tendency to eliminate the repeated shall. The 1908 RLDS edition restored the original shall here in Ether 3:22. For another example of the loss of a repeated shall, see under Helaman 9:33.
Also with respect to this passage, Ross Geddes (personal communication, 28 November 2004) wonders about the meaning of the initial subordinate clause in this verse, “and behold when ye shall come unto me”; the text, as it stands, doesn’t seem to make much sense. Contextually, the passage seems to be saying that when the brother of Jared has seen and heard these things, he should write them and seal them up. Geddes suggests emending the clause “when ye shall come unto me” by replacing ye with these and me with thee (thus “and behold when these shall come unto thee”).
Heather Hardy (personal communication, 12 May 2006) also wonders if there isn’t some mistake in the specific phrase “come unto me”. The next chapter seems to imply that what is meant here in Ether 3:22 is that the brother of Jared should write up these things after going down from the mount:
This passage would imply that the text in Ether 3:22 should read something like “and behold when ye shall go down from me”, but Hardy recognizes that a change of “go down from me” to “come unto me” seems rather implausible. In any event, the current reading in Ether 3:22 can’t reasonably refer to the brother of Jared’s death, nor figuratively to when he “comes unto Christ” (that is, when he accepts Christ), since he already has.
One wonders whether any other conjectural emendation might work better here, perhaps a change of a single word or a change that we could find evidence for in the history of the text. Until such an emendation is found, it is probably safest to retain the earliest reading here in Ether 3:22. Perhaps there is some other way to interpret the reading as it currently stands.
Summary: Maintain in Ether 3:22 the repeated shall, the reading of the earliest text; also retain the difficult subordinate clause “and behold when ye shall come unto me”; thus far no plausible reading or emendation has presented itself that would make sense out of this clause.