Living in the Realm Where God Lives
On either side of the river, the tree of life with its twelve kinds of fruit, yielding its fruit each month. The leaves of the tree were for the healing of the nations. No longer will there be anything accursed, but the throne of God and of the Lamb will be in it, and his servants will worship him.
Revelation 22:2-3
Eternal life is life and life more abundantly—it is being alive in the realm where God lives (John 10:10). Life is walking with God in unending communion, enjoying his unlimited blessing, experiencing his unconditional love, and receiving his undeserved grace. The opposite of eternal life is not finite life, but eternal death. The eternal life that Christ offers is entire salvation of the whole being including conversion and new birth as well as final glorification (John 3:16).
Why can we have the tree of life? Because Jesus Christ climbed the cross, the tree of death. And because Jesus climbed the tree of death you can have the tree of life.
Tim Keller, “The Garden: City of God,” Pastor, Redeemer Presbyterian Church, Manhattan, N.Y.