I just wanted to say, Eve was deceived. See, it says that God told Adam, but there is no record of God telling Eve. Eve was deceived, and Adam was punished more because it was his seed that lost eternal life. Adam had to have been with her. He didn't stop her, and he waited until she tested it before he did. The lack of eternal life comes through the Y Chromosome.
Romans 5:12-20 New International Version (NIV)
"Death Through Adam, Life Through Christ
12 Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all people, because all sinned—
13 To be sure, sin was in the world before the law was given, but sin is not charged against anyone’s account where there is no law. 14 Nevertheless, death reigned from the time of Adam to the time of Moses, even over those who did not sin by breaking a command, as did Adam, who is a pattern of the one to come.
15 But the gift is not like the trespass. For if the many died by the trespass of the one man, how much more did God’s grace and the gift that came by the grace of the one man, Jesus Christ, overflow to the many! 16 Nor can the gift of God be compared with the result of one man’s sin: The judgment followed one sin and brought condemnation, but the gift followed many trespasses and brought justification. 17 For if, by the trespass of the one man, death reigned through that one man, how much more will those who receive God’s abundant provision of grace and of the gift of righteousness reign in life through the one man, Jesus Christ!
18 Consequently, just as one trespass resulted in condemnation for all people, so also one righteous act resulted in justification and life for all people. 19 For just as through the disobedience of the one man the many were made sinners, so also through the obedience of the one man the many will be made righteous.
20 The law was brought in so that the trespass might increase. But where sin increased, grace increased all the more, 21 so that, just as sin reigned in death, so also grace might reign through righteousness to bring eternal life through Jesus Christ our Lord."