Gen 2:16-17 . . The Lord God commanded the man, saying: Of every tree of the garden you are free to eat; but as for the tree of knowledge of good and bad, you must not eat of it; for in the day you eat of it, you shall die.

Gen 3:4 . . And the serpent said to the woman: You are not going to die,

Here we have the beginnings of what's known as a half-truth; which Webster's defines as a statement that is only partly true and that is intended to deceive people. In other words: half-truths contain a kernel of truth but not the whole truth and nothing but the truth.

The Serpent somehow knew that the forbidden fruit itself wasn't lethal, i.e. Eve wouldn't die from eating it like hemlock or a Night Cap mushroom. He was 100% right about that. Her death, though related to eating the fruit, would come upon her from a very different direction; one that Eve apparently never suspected; though it was right under her nose the whole time.