[nkoren]

The reference -- and the concern about tinkering with the tree of life -- goes a bit further back:

"And YHVH 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 forever -- let us send 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 Cherubim, and a flaming sword which turned every way, to keep the way of the tree of life." -- Genesis 3:22-3:24

(Nb.: Citation of religious text does not imply endorsement thereof.)