Textual: Verses 2-5 comprise the public’s declaration of their willingness to enter in to a covenant. The precision of the words, as well as the introduction “they all cried….” indicates that Mormon is citing the record of the plates at this point. While the precision of the words indicates that Mormon is copying his source, it also points out that this is a crafted and stylized account. The “one voice” with which they all “cried” would have been impossible to accomplish literally. The very fact that messengers were sent among them requires that those messengers reach different clans at different times, and there would be a physical impossibility of responding in a chant – unless this were again a written response that they chanted.
While it is possible that even this is a crafted part of public ritual, it would appear to diminish the spiritual power of the occasion to presume so much of it. The rest of the text appears to suggest that this was a free-will covenant, and not one orchestrated by pomp and circumstance. The declaration of their faith on the words of the king (verse 4) would be accurate, but given Benjamin’s humility, not a likely thing for Benjamin to have written. Had Benjamin crafted the response, it would have the people believing the words of the angel through the king.
The most likely hypothesis is that the intent of the people spoke from their hearts in “one voice” and this stylized account of that occasion was written down later as the official rendition of what had occurred.
Social: In the context of Benjamin’s emphasis on the social unity of his people, and particularly with his use of the “evil spirit” as the temptation that leads to contention, it is possible to read this declaration of their desire to change their social interactions. When they say that they have had a mighty change, this may mean that the prejudices that Benjamin had chastised them for, such as withholding from the needy, were driven from them. That they no more would do evil, would be that they would no more follow that evil spirit in the contentions between the old ways and the new covenant.
Spiritual: Regardless of how this particular passage would have impacted Benjamin’s people, it is a powerful statement to modern readers. The process of repentance is indeed one of a “mighty change.” The old man must be removed, and we must be renewed in Christ. Just as Benjamin describes their experience in terms of a transformation (they are now children of Christ - verse 7) we too must be transformed.
The symbolism for modern still retains the imagery of birth, but now those symbols have been fused with the symbolic cleansing of baptism. Modern baptism takes on a wider range of symbolic meanings, from cleansing to new birth (both in the coming up out of the water, and in the water that accompanies birth).