One scholar noted that there might be a connection between the fig leaves used by Adam and Eve for hiding their nakedness after the fall and the mention in Revelation chapter 22 of the leaves for healing (Thomas Howe, Ph.D., Professor at Southern Evangelical Seminary, Charlotte, NC). God uses pictures of leaves falling or withering in Isaiah 34:4 where the host of heaven falls like leaves from the fig tree under God's judgment on the nations, and in Jeremiah 8:13, where the leaves have withered in Judah due to Israel's apostasy. God predicts the restoration of the garden, or perhaps man's re-access to the garden, in Ezekiel chapter 47 and Revelation chapter 22. Just as leaves were used by man as a covering in the fall due to shame before God, so leaves will be redeemed to represent healing or restoration in the time of total redemption.
The physical properties of leaves in ancient times were utilized for ailments or injuries. Blackberry leaves were chewed for bleeding gums or used for burns; olive leaves were an astringent; and sycamore and walnut leaves were applied to wounds (Ryken, 497-98). In Ezekiel 47:12 and its mirror passage, Revelation 22:2, we see the tree of life with leaves for healing, not just for physical healing, but for the healing of final redemption and restoration (The Hebrew word for 'healing' in Ezekiel 47.12 has meanings that include to "prosper, to sustain life, or to nourish," [TWOT, Vol. 1, 280]).
To use leaves as part of this imagery makes sense in light of Romans 8:19-22, which speaks of creation's fall (due to man's sin) and yearning for redemption. The trees are even depicted as longing for God's judgment: "Then the trees of the forest will sing with joy before the Lord; for He is coming to judge the earth" (1 Chronicles 16:33 NASB).
The trees in the Ezekiel passages, like the Garden of Eden being watered by a river (Genesis 2:10), are on both sides of the river bearing fruit very month. In the future vision of Revelation 22:2, the tree of life is on each side of the "water of life" that flows from the throne of "God and the Lamb" and runs through the middle of the street, bearing twelve kinds of fruit. So we see a parallel between the trees by a river in Genesis, where the tree of life was denied and leaves were used to hide from God to the trees by the river in Ezekiel with leaves of healing; and a final parallel in Revelation to the tree of life on each side of a river "of life" with leaves for healing.
Expectations of restoration from death are seen in passages such as Psalms 49:15 ("But God will rescue me from the power of death" ESV), Psalms 17:15, Psalms 73:23-36, and Hosea 6:1, 2. "This expectation is neither magical nor mythical not speculative nor mystical. It is a certainty produced in the righteous by the concept of grace alone" (Quoting Bultmann, TDNT, II, 848, in TWOT, 280). God, as always, is the source of life, nourishment, restoration, and redemption.
Trees, a part of creation that played such a crucial role in the fall, that were used as shade for the worship of gods other than the one true living I AM God, and whose wood was carved to form idols, are now producing fruit. The forbidden tree that led to sin became the true tree of life when Jesus died on the cross, atoning for sins. The leaves that covered Adam and Eve are gone, replaced by leaves that heal. The future restoration is complete, and those redeemed in Christ are now in a restored creation with God.
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