I find it interesting that after they ate from the tree God said:
"The man has now become like one of us, knowing good and evil"
Isn't this exactly what Satan had said would happen?
This is something that has always intrigued me and i've speculated about. My thought is the "fruit" actually contained something that caused a mental change over Adam and Eve. Like many other foods today that can have emotional, physical, or mental effects on a person. That would explain the question Jehovah asks them when they were hiding from him, "Who told you you were naked? From the tree of the knowledge of good and bad, did you eat?"(Gen. 3:8-13). Which would also show that Jehovah didn't "foreordain" their downfall.
The thought of them knwing Good and Evil meant that they would now decide for themselves what was right and wrong; independence from God, oppposed to dependence and instruction from Jehovah. Thus, "sin" (the selfish tendencies and emotions that dominates thinking today) crept into the world.
Shortly thereafter, we see a rapid decline in moral values. Murder, Idolatry, Ruthless killing, theft, ect. The depraved world had declined to the point that Jehovah spared Enoch from a horrible death by the hand of his enemies and euthanized him.
Eve was under the assumption that eating the fruit would kill her instantly. So both God and Satan were correct.
Satan said that you couldn't die by eating the fruit. That was true, the fruit wasn't poisonous.
God said that by eating the fruit they would die. It was the act of disobedience that led to their eventual death.
Pure semantics. This is similar to a parent telling a teen, "If you keep smoking, you're going to die." The child isn't going to keel over the moment his lips touch a cigarette. No, but the effects of lung cancer due to smoking would be the "effect". Thus, Adam and Eve were cut-off from the life-sustaining fruitage found in the Garden of Eden and they eventually died. Remember also, time, days, and speed to Jehovah is something we can't comprehend. The Bible says, "A day with Jehovah is as a thousand years." (2Pet.3:8)
Satan is called the father of the lie, but off the top of my head, I can't think of any place in the bible where he actually lies.
The first lie Satan told was emphatically stating, "You POSITIVELY will not die.". Are they still alive today? Did Satan lie about Job (Job1:11)?
And as for why did Satan stop tempting Jesus? Because Jesus asked him to leave at Matthew 4:10. Keep in mind that Jesus was at this time surrounded by angels waiting to see the outcome of this temptation as is pointed out in verse 11. You could either say that Satan respected Jesus' request or he didn't want to get pounded on by a legion of angels.
You could also say that Satan needed to regroup if he was going to prove true his claim that any human (even a perfect one like Jesus) would turn against Jehovah if the price was right. It does say at Luke 4:13 that Satan left until "another convenient time.". Satan didn't fear getting pounded. They knew their destruction was centuries into the future. Look at the evil committed by Satan and his demons since his rebellion in Eden: Raped and impregnated women in Noah's day, left their hybrid children and wives to die in the flood, Murdered Jobs children, servants, and physically abused him, and demonic possession of weaker humans to name a few. Other than that, you'd have us believe he's really a nice guy?