Genesis 3:22-24 And the Lord God said, Behold, the man is become as one of us, to know good and evil: and now, lest he put forth his hand, and take also of the tree of life, and eat, and live for ever: Therefore the Lord God sent him forth from the garden of Eden, to till the ground from whence he was taken. So he drove out the man; and he placed at the east of the garden of Eden Cherubims, and a flaming sword which turned every way, to keep the way of the tree of life.

To get to eternal life, we must get past a flaming sword. A sword cuts, and a flame destroys. To get to Heaven our flesh is cut away and destroyed. The clues pointing to Separation Atonement are everywhere in the Bible.