The cherubim, God's angels of covering, kept the way to the Tree of Life with flaming swords. If fallen man had been a partaker of the Tree of Life, he would live forever without having to go through the Cross. If Adam and Eve had partaken of the Tree of Life after they had eaten at the Tree of the Knowledge of Good and Evil, they would have lived forever in the state they were in after eating knowledge, knowing good and evil but not having life. The cherubim protected that way so they could not come in to eat unless they had a covering. God killed an animal and made skins to clothe the man and the woman, giving them a covering. Two naked people who walked in human depravity could now partake of the Tree of Life because of the covering. God never mentioned anything more about Adam and Eve after this covering, for the shedding of blood brought remission and the covering hid them in God by mercy.
Consider how Adam and Eve were hiding and alone after they had sinned, and God sought after them. He found them and clothed them with a covering that came through the Blood. We receive that same covering through the shed blood of the Lamb of God, a reconciliatory covering that not only gets us to Heaven but brings us to God in our earthly experience; a covering that reconciled the prodigal to the Father's love, grace, and mercy.
Though no man himself seeks after God, God sought us out and brought us home to experience the freedom of Sonship with all the privileges of that heavenly home.