Then the Lord God said, “Behold, the man has become like one of us in knowing good and evil. Now, lest he reach out his hand and take also of the tree of life and eat, and live forever—” therefore the Lord God sent him out from the garden of Eden to work the ground from which he was taken. He drove out the man, and at the east of the garden of Eden he placed the cherubim and a flaming sword that turned every way to guard the way to the tree of life. - Genesis 3:22-24

There is a strong impulse to tie this "knowing good and evil" to the nakedness of the first couple (Gen 2:25; 3:7). This is unfounded and instead points to their knowledge of rejecting God's will. This is the definition between good and evil: God's will.

Again, this text provides us with insight into the poetic nature of its discourse. Could a tree truly bring forth eternal life apart from the saving work of Jesus Christ? Of course not. Instead it is best to read that from the foundation of the world this tree was laid. And in the proper time it was made manifest to the world (Heb 1:1-2) that the church could receive the promises of this tree of life (Rev 2:7; 22:2, 14). 

In a practical manner, God's denial of the tree of life speaks to His concern over or condition. Man needed to be restored as new creation (2 Cor 5:17) before being imparted with the eternal life of Christ Jesus. Death was to be defeated (Heb 2:14-15) before life was offered freely to all.

*The Bible Blogging Commentary is a slow and simple treading of the Scriptures. No quotes from other theologians and no explicit Greek/Hebrew lessons.*