'Tree of Life' in the Bible

And out of the ground LORD God made to grow every tree that is pleasant to the sight, and good for food, also the tree of life in the midst of the garden, and the tree of the knowledge of good and evil.

And LORD God said, Behold, the man has 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 forever--

So he drove out the man. And he placed at the east of the garden of Eden the Cherubim, and the flame of a sword which turned every way, to guard the way of the tree of life.