Genesis 3:22 - 24
ESV - 22 Then the Lord God said, "Behold, the man has become like one of us in knowing good and evil. Now, lest he reach out his hand and take also of the tree of life and eat, and live forever - 23 Therefore the Lord God sent him out from the garden of Eden to work the ground from which he was taken.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.