Life is a person, the Lord Jesus Christ, who is shown in type as a tree located in the midst of the Garden of Eden. This tree is a fruit tree which God indicated that man could freely eat of. In fact there were many trees in the garden which were delightful for man to enjoy. These trees represent all the divine attributes of God which He intended for man to enjoy, assimilate and finally express. The Lord said in  John 6:51, "I am the living bread which came down out of heaven; if anyone eats of this bread, he shall live forever; And the bread which I will give is My flesh, given for the life of the world. 6:54 He who eats My flesh and drinks My blood has eternal life, and I will raise him up in the last day. 
6:55 For My flesh is true food, and My blood is true drink.  
6:56 He who eats My flesh and drinks My blood abides in Me and I in him. 
6:57 As the living Father has sent Me and I live because of the Father, so he who eats Me, he also shall live because of Me. 
6:58 This is the bread which came down out of heaven, not as the fathers ate and died; he who eats this bread shall live forever. 
 So here we see that the Lord characterizes Himself as the fruit of the wheat which has the power to convey eternal life. All one must do is eat and continue to eat this bread. In many other verses in the Bible we are shown that to eat the Lord is to contact Him with our regenerated spirit. When our spirit is regenerated it is regenerated by Christ Himself as the life-giving Spirit who comes into our human spirit. Since He is living there it is easy to contact Him and thus to "eat" Him. All we need to do is exercise our spirit to call upon Him.

But we must not forget that Adam and Eve did not eat from the tree of life. They disobeyed God and instead obeyed the serpent, by whom they became enslaved because they lost the function of their human spirit and had no way to contact God until the Lord Jesus gave Himself as a sacrfice to pay the death penalty God had pronounced as a result of eating from the tree which represented independence from God. Nevertheless God showed Adam and Eve His intention to redeem them when the Lord died for them by showing them that a blood sacrifice, in this case an animal sacrificed to obtain the skin, would cover them until the real covering, the Lord as the Savior, would come. 

Nevertheless, since Adam and Eve were unable to give life to their offspring, all subsequent people were born in the same dead condition of Adam and Eve. Later in the New Testament we will see that the reality of this dead condition is that man can only live by the death poisoned soul until there is the regeneration by the life-giving Spirit. If we would have life we must recognize our real situation.