They will be the visible representatives of the kingdom of heaven.

These are the ones who shall administer the affairs of earth under the direction of the Lord.
[581]We therefore see that there are two phases of God's kingdom: the heavenly, which is invisible; and the earthly, which is visible, the faithful prophets of old, namely, the ancient worthies, representing the Lord in this regard.
[582]The Lord through his prophet Zechariah gives a wonderful picture of the establishment of this kingdom and of the blessings that will come.
The prophecy is written in highly symbolic phrase.

It reads: "His feet shall stand in that day upon the mount of Olives, which is before Jerusalem on the east, and the mount of Olives shall cleave in the midst thereof toward the east and toward the west, and there shall be a very great valley; and half of the mountain shall remove toward the north, and half of it toward the south.

And ye shall flee to the valley of the mountains; for the valley of the mountains shall reach unto Azal: yea, ye shall flee, like as ye fled from before the earthquake in the days of Uzziah king of Judah; and the Lord my God shall come, and all the saints with thee." (Zechariah 14:4,5) "His feet" in this prophecy represent Jehovah's feet; while mountain symbolizes kingdom.

The olive is a symbol of light, peace, and divine blessing; hence the picture is that Jehovah's authority, represented by his feet, will be established upon earth, by a kingdom of light, peace, and blessing.