A thorough look at 3 Nephi 20:26-28

I have learned that when similar statements are repeated, the small differences might be meaningful. Therefore I have been looking at 3 Nephi 20:26-28 on and off for days. I'm still not sure I have fully understood the passage. But there is a certain repeated structure in these verses that I will try to dissect with color-coding. I also break it up into 4 sentences, a bit different from the verse breaks.

And then shall the work of the Father commence at that day, even when this gospel shall be preached among the remnant of this people.

Verily I say unto you, at that day shall the work of the Father commence among all the dispersed of my people, yea, even the tribes which have been lost, which the Father hath led away out of Jerusalem.

 

Yea, the work shall commence among all the dispersed of my people, with the Father to prepare the way whereby they may come unto me, that they may call on the Father in my name.

 

Yea, and then shall the work commence, with the Father among all nations in preparing the way whereby his people may be gathered home to the land of their inheritance.

Each segment starts with "the work" of/with the Father commencing. The work has been explained already in this chapter and it consists of God fulfilling his covenant with the House of Israel (see verse 7). The work will occur "among" someone, but it varies in the different segments. Finally, there is a description of an occurrence involving these people.

One thing I noted is how the verses start out with "this people", then there is "my people" and finally "his people", referring to the Father. In other words, "the work" expands in scope and those involved. 

As you can see, there are four "work shall commence" statements but only three variations in references to people and three descriptions of occurrences. This is because the second sentence is only a clarification of who "the dispersed of my people" really are. They are "the tribes which have been lost, which the Father hath led away out of Jerusalem. The "work shall commence" statement is just repeated before the description of what will happen to them. So the Father's work of fulfilling the covenants with the House of Israel, as described in these verses, can be summarized as follows.

People	Occurrence
A remnant of the Nephites/Lamanites	The gospel shall be preached among them
The dispersed of Christ’s people, the lost tribes	Come unto Christ and call on the Father in His name
The Father’s people among all nations	Gather to the land of their inheritance

Like I said, I don't know if I understand everything about this, but I find it interesting that after "this people" hear this gospel preached, Christ starts talking about "my people". And after Christ's people pray to the Father, he starts talking about the Father's people. 

These verses also teach us that the work of fulfilling the Father's covenant with the House of Israel is all about gathering, both spiritually and physically. The spiritual gathering happens when "the dispersed" come unto Christ. The physical gathering happens when they gather to the land of their inheritance. This does not happen by force but by preparing the way. As the link explains, preparing the way enables the transition from a wilderness to a fruitful place, from spiritual wasteland to Zion.