Genesis 2:9

Every tree that is pleasant to the sight, and good for food. — It has often been noticed that while the ancients do not seem to have had much taste for the beauty of the landscape, they greatly admired large and umbrageous trees. This feeling seems like a reminiscence of the joy of our first parents when they found themselves in a happy garden, surrounded by trees, the beauty of which is even more commended than the fact placed second, that they supplied wholesome and nutritious food. Two trees in the centre of the garden had marvellous qualities; for “the tree of life” ad the power of so renewing man’s physical energies that his body, though formed of the dust of the ground, and therefore naturally mortal, would, by its continual use, live on for ever. The other, “the tree of knowledge of good and evil,” must have acquired this name after the fall. As long as Adam and Eve were in their original innocence they had no knowledge of evil, nor could any mere mental development bestow it upon them. They must either feel it in themselves, or see it in others, before they could know it. We conclude, then, that this was the tree to which God’s command, that they should not eat of it (comp. Genesis 3:3), was attached; and only by the breach of that command would man attain to this higher knowledge, with all the solemn responsibilities attached to it. Besides this each tree had a symbolic meaning, and especially the tree of life (Revelation 2:7; Revelation 22:2). The Chaldean legends have preserved the memory of this latter tree, and depict it as the Asclepias acida, whence the soma juice is prepared.