God put the tree of knowledge of good and evil in the Garden of Eden to give Adam and Eve a choice to obey Him or disobey Him. Adam and Eve were free to do anything they wanted, except eat from the tree of knowledge of good and evil. Genesis 2:16-17, “And the LORD God commanded the man, ‘You are free to eat from any tree in the garden; but you must not eat from the tree of the knowledge of good and evil, for when you eat of it you will surely die.’” If God had not given Adam and Eve the choice, they would have essentially been robots, simply doing what they were programmed to do. God created Adam and Eve to be “free” beings, able to make decisions, able to choose between good and evil. In order for Adam and Eve to truly be free, they had to have a choice.

There was nothing essentially evil about the tree or the fruit of the tree. It is unlikely that the fruit, in and of itself, gave Adam and Eve any further knowledge. That is, the physical fruit may have contained some vitamin C and some beneficial fiber, but it was not spiritually nutritious. However, the act of disobedience was spiritually deleterious. That sin opened Adam’s and Eve’s eyes to evil. For the first time, they knew what it was to be evil, to feel shame, and to want to hide from God. Their sin of disobeying God brought corruption into their lives and into the world. Eating the fruit, as an act of disobedience against God, was what gave Adam and Eve the knowledge of evil—and the knowledge of their unclothedness (Genesis 3:6–7).

God did not want Adam and Eve to sin. God knew ahead of time what the results of sin would be. God knew that Adam and Eve would sin and would thereby bring evil, suffering, and death into the world. Why, then, did God allow Satan to tempt Adam and Eve? God allowed Satan to tempt Adam and Eve to force them to make the choice. Adam and Eve chose, of their own free will, to disobey God and eat the forbidden fruit. The results—evil, sin, suffering, sickness, and death—have plagued the world ever since. Adam and Eve's decision results in every person being born with a sin nature, a tendency to sin. Adam and Eve's decision is what ultimately required Jesus Christ to die on the cross and shed His blood on our behalf. Through faith in Christ, we can be free from sin's consequences, and ultimately free from sin itself. May we echo the words of the Apostle Paul in Romans 7:24-25, "What a wretched man I am! Who will rescue me from this body of death? Thanks be to God—through Jesus Christ our Lord"

Reference from GotQuestions.org

In Summary!