The first sin in the Bible is when Eve listened to the Serpent . You want to mince words and assign sin to Eve for her response to the Serpent as being inaccurate/lie. Hogwash , Eve damn well knew exactly what God had said as did the Serpent, the first real sin in the Bible happens where the first question mark appears which makes the Serpents question in itself the first sin. How so ? To question God is to imply He doesnt mean what He said, the Serpent knew God meant what He said but it got Eve to listen and eventually doubt God . We all today are paying for her doubt of what God said. Eve sinned initially by even entertaining the idea questioning what God said, hence we have the goal of the Sepent - to make people doubt what God said.
Rrhain: God in mercy delayed the penalty of death, Adam and Eve BEGAN to die that very day because they were banished from the Garden , which represents the source of their life - God. Eventually they both died but that is not in dispute. For you to casually accuse God of lying reveals a lack of basic Bible knowledge - it is impossible for God to lie. You do not understand. God did not want them to eat from the tree because He said so ! Eve had no business even going near the thing that God said not to have anything to do with. God didnt want them to have the knowledge of good and evil because there is no power in that knowledge to choose the good over the evil , the entire record of the O.T. on proves that.