With the creation of a new heaven and new earth, God restores Creation as it was originally intended and fulfills His covenant with Abraham. Third heaven and the new earth are now united as the abode of God.

Previously corrupted, the created image of God is recovered and his relationship with God restored (Rev 21:3-7; 22:3-5; Gen 1:26-27; Rom 8:28-30).

Glorified saints have access to the Tree of Life (Rev 22:2; Gen 3:22-24) and something never mentioned before, the Water of Life (Rev 21:6; 22:1, 17).

All of the national promises to Abraham were fulfilled:

".. you shall be a blessing" (Gen 12:2)

"… And in you all the families of the earth will be blessed." (Gen 12:3)

Through Abraham and his descendants, specifically through Jesus Christ, the world will be blessed.

Through David, this promise is elaborated to include a King from his royal lineage, who will have a kingdom that will endure forever (Gen 17:15-16; 2 Sam 7:16; Ps 89:3-4; Luke 1:31-33), and from the line of David was Jesus Christ.

Despite the failure of the nation of Israel to keep their promise of the Mosaic Covenant, God unilaterally makes a New Covenant mediated through Jesus Christ (Jer 31:31-34; Ezek 36:25-28; Luke 22:20), and bestows the Holy Spirit.

"To your descendants I have given this land, from the river of Egypt as far as the great river, the river Euphrates: the Kenite and the Kenizzite and the Kadmonite and the Hittite and the Perizzite and the Rephaim and the Amorite and the Canaanite and the Girgashite and the Jebusite." (Gen 15:18-20)

Abraham's descendants are promised land that extended from Egypt to include Jordan, Lebanon, Syria, western parts of Iraq and northern parts of Saudi Arabia (Gen 12:1, 7; 13:14-15, 17; 15:17-21; 17:8).

God fulfills this promise of land with new Jerusalem. Although, new Jerusalem is a square (1500 miles x 1500 miles), its area encompasses the entire land, between the Nile and Euphrates rivers, promised by God!

For deeper study:

New Heaven and New Earth

Divine Covenants… the basis for a plan of salvation