I've always heard it explained that the lie Satan told Eve that really was the lie is that they would be as gods.
For God doth know that in the day ye eat thereof, then your eyes shall be opened, and ye shall be as gods, knowing good and evil. (said the serpent)
BUT that was true:
And the LORD God (Jehovah elohiym) 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 for ever:
You know the rest, God sent them out of the garden and forbid them from access to the tree of life. Therefore, this would be better called the temptation and not the lie.
Now, the lie:
Eve said that God said:
But of the fruit of the tree which [is] in the midst of the garden, God hath said, Ye shall not eat of it, neither shall ye touch it, lest ye die.
Satan says:
And the serpent said unto the woman, Ye shall not surely die:
God said:
In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou [art], and unto dust shalt thou return.
The lie was that they would not die, but the temptation to disobey God was that they would be as gods. (which was true in the knowledge of good and evil respect....God even says so).
It got me to thinking about a couple of knowledge verses:
For in much wisdom is much grief: and he that increaseth knowledge increaseth sorrow. Ecc 1:18
Wisdom [is] the principal thing; [therefore] get wisdom: and with all thy getting get understanding. Prov4:7
I believe in the sovereignty of God and that if He hadn't intended Eve to eat, and later Adam, it wouldn't have happened. God wanted us to be wise, but why by disobedience?
For God has shut up all in disobedience so that He may show mercy to all. (Romans 11:32)
Perhaps?