Doctrine and Covenants 65

How does the kingdom of God on earth prepare the world for the Savior's return?

"Revelation on prayer given through Joseph Smith the Prophet, at Hiram, Ohio, October 30, 1831.

1–2, The keys of the kingdom of God are committed to man on earth, and the gospel cause will triumph; 3–6, The millennial kingdom of heaven will come and join the kingdom of God on earth.

1 Hearken, and lo, a voice as of one sent down from on high, who is mighty and powerful, whose going forth is unto the ends of the earth, yea, whose voice is unto men—Prepare ye the way of the Lord, make his paths straight.

2 The keys of the kingdom of God are committed unto man on the earth, and from thence shall the gospel roll forth unto the ends of the earth, as the stone which is cut out of the mountain without hands shall roll forth, until it has filled the whole earth.

3 Yea, a voice crying—Prepare ye the way of the Lord, prepare ye the supper of the Lamb, make ready for the Bridegroom.

4 Pray unto the Lord, call upon his holy name, make known his wonderful works among the people.

5 Call upon the Lord, that his kingdom may go forth upon the earth, that the inhabitants thereof may receive it, and be prepared for the days to come, in the which the Son of Man shall come down in heaven, clothed in the brightness of his glory, to meet the kingdom of God which is set up on the earth.

6 Wherefore, may the kingdom of God go forth, that the kingdom of heaven may come, that thou, O God, mayest be glorified in heaven so on earth, that thine enemies may be subdued; for thine is the honor, power and glory, forever and ever. Amen." (Doctrine and Covenants 65)

And here's the commentary entitled: "The kingdom of God on earth prepares the world for the Savior’s return." : 

"Doctrine and Covenants 65 gives an inspiring description of the mission of the Lord’s Church in the latter days. Consider searching this section, looking for answers to questions like these: What does the Lord want His kingdom to accomplish on the earth? What does He want me to do to help?

See also “Prepare Today for the Second Coming” (video), ChurchofJesusChrist.org."

The Lord wants His kingdom to go forth upon the earth and the inhabitants of the earth to receive it and be prepared for the Savior's return. He wants me to pray and proclaim His wonderful works among the people to help in spreading His kingdom. The kingdom of God on earth is able to prepare the world for the Savior's Second coming on earth by transforming their lives as they choose to live by the principles and doctrines of the gospel of Jesus Christ.