Fire in the Bible always refers to the holiness of God. Because God is a consuming fire (Deut. 4:24; 9:3; Heb. 12:29), anything common, unclean, or sinful is consumed by Him (Lev. 10). After man ate of the tree of the knowledge of good and evil and received the things that are apart from God, he became unholy, worldly, and common. Hence, God must guard the way to the tree of life by His holiness, not allowing sinful man to come near to Him lest he be consumed by the fire of His holiness.
The third item that guarded the way of the tree of life was the sword. The sword signifies God’s righteous killing. The sword in Genesis 3 indicates that to be killed is the punishment meted out to the sinner by God’s righteousness (Lam. 3:42-43; Rom. 2:5). Since God is righteous, He cannot consider a sinful one as one who is without sin. Since man was sinful, God had to inflict a penalty, and His penalty was to kill man. Therefore, God’s guarding the tree of life with the sword means that God’s righteousness would not allow the fallen sinner to contact the tree of life; otherwise, man would be smitten by the sword of God’s righteousness.
Thus, because of man’s fall, God drove man out of the Garden of Eden and placed the cherubim and the flaming sword which turned every way, to guard the way of the tree of life. That is, He closed the way to the tree of life by His glory, holiness, and righteousness, keeping man away from the tree of life and not allowing the fallen sinner to contact Him and obtain Him as life. It was not until the accomplishment of Christ’s redemption, which satisfied the requirements of God’s glory, holiness, and righteousness, that the way to the tree of life was opened once again.
In the entire Bible God made eight covenants with man: seven in the Old Testament and one in the New Testament. The first covenant which God made with man was a covenant that God made with the created man. The One who made this covenant was Jehovah God, the One who always is and the mighty One who is faithful. The one with whom the covenant was made was the created man who was without God’s life and without sin, but who had a spirit and a free will and who was assigned to dress and guard the garden of God. God made a covenant with him that by eating he should receive the tree of life, which signifies God as the source of life, so that God might enter into him to be joined and mingled with him, thus fulfilling God’s purpose in creating man. Furthermore, God wanted man to reject the tree of the knowledge of good and evil, which signifies Satan as the source of sin and death, lest Satan’s evil, poisonous element should enter into man, thus damaging the upright and pure man whom God created for His eternal purpose. Eventually, man acted contrary to God’s covenant and, having been deceived by the serpent (the Devil), ate of the tree of the knowledge of good and evil, thus receiving Satan and having sin and death. Hence, man was driven out of the Garden of Eden and was kept away from the tree of life, that is, kept away by the cherubim, which signify God’s glory, by the flame, which signifies God’s holiness, and by the sword, which signifies God’s righteousness. It was not until the accomplishment of Christ’s redemption, which satisfied the requirements of God’s glory, holiness, and righteousness, that the way to the tree of life was opened once again.