The interchange between the Lord and the servant is instructive. The Lord suggests that the Lamanites be destroyed for their wickedness. The servant intervenes on their behalf, requesting of the Lord that more work be done to save the wicked part of the tree that perhaps it may bring forth good fruit. This is exactly what happened. In more than one place in the Book of Mormon, the Nephite prophets prayed on behalf of their Lamanite brethren. They prayed that the Lord would show mercy to them in the last days and bring them to a knowledge of the truth.
’And after I, Enos, had heard these words, my faith began to be unshaken in the Lord; and I prayed unto him with many long strugglings for my brethren, the Lamanites…
And now behold, this was the desire which I desired of him--that if it should so be, that my people, the Nephites, should fall into transgression, and by any means be destroyed, and the Lamanites should not be destroyed, that the Lord God would preserve a record of my people, the Nephites; even if it so be by the power of his holy arm, that it might be brought forth at some future day unto the Lamanites, that, perhaps, they might be brought unto salvation—’ (Enos 1:11,13)
’And behold, these things which we have desired concerning our brethren, yea, even their restoration to the knowledge of Christ, are according to the prayers of all the saints who have dwelt in the land.’ (Mormon 9:36)
The other interesting thing to note is that the prophets can, at times, stay the hand of the Lord, intervene for their people, and request the mercy of the Lord on their behalf. Such an exchange occurred between Moses and the Lord after the children of Israel rebelled in the wilderness of Sinai. The Lord was angry and wanted to destroy the people. Moses intervened as follows:
’And the Lord said unto Moses, How long will this people provoke me? and how long will it be ere they believe me, for all the signs which I have shewed among them?
I will smite them with the pestilence, and disinherit them, and will make of thee a greater nation and mightier than they.
And Moses said unto the Lord, Then the Egyptians shall hear it, (for thou broughtest up this people in thy might from among them;)…
And now, I beseech thee, let the power of my Lord be great, according as thou hast spoken, saying,
The Lord is longsuffering, and of great mercy, forgiving iniquity and transgression, and by no means clearing the guilty, visiting the iniquity of the fathers upon the children unto the third and fourth generation
Pardon, I beseech thee, the iniquity of this people according unto the greatness of thy mercy, and as thou hast forgiven this people, from Egypt even until now.
And the Lord said, I have pardoned according to thy word.’ (Num 14:11-20)