The serpent was more SUBTLE than any beast... the devil almost never uses an in your face frontal assault tactic as his first attempt. We are naturally repulsed by full blown evil and it takes a lot of conditioning to cause people to accept it in its raw form. The serpent questions Eve with a perversion of God's instructions, he asks hath God said Ye shall not eat of EVERY tree in the garden? Eve's answer shows two things, 1 Adam had told her not to eat the fruit that God told him not to eat, 2 Either Adam went beyond God's command and told her that even to touch it would mean death or she assumed it for herself. He then Questions God's motives for keeping them from that particular tree. It probably didn't happen this way but i can imagine the devil holding the fruit and Adam and Eve seeing that he didn't die right away, as they thought he should, gave weight to his words.
  However it happened they believed the devil instead of God and if you think about it, that is the source of all sin. After they ate the fruit their eyes were opened and they became ashamed and tried to cover themselves. What follows is textbook material on how not to react when you sin. They covered themselves in an inappropriate way though sense, when God gave them animal skins and did not reprimand them about their attempt i won't scold them either. They then hid when God was looking for them, have you ever wondered what would have happened if they would have first looked for God to confess their sin? Next, when God questions them the only one to remain silent and not blame someone else was the serpent, maybe he knew God well enough to know not to dig the hole any deeper. Notice that God followed the chain of command that He Himself had set up. First He asked Adam what happened, then Eve but when He got to the serpent, punishment began. The serpent was cursed above all animals, made to go on his belly and eat dust (man is made from dust), and made the enemy of the woman's seed, "IT shall bruise thy head , and thou shalt bruise HIS heel." To the woman God said "I will greatly multiply thy sorrow and thy conception ; in sorrow thou shalt bring forth children; and thy desire shall be to thy husband, and he shall rule over thee." Just a note about God's statement, if He multiplied her conception and sorrow could it be that she had already had children and that it was painless? Also, when God said he shall rule over thee, perhaps because of sin the relationship between man and woman changed and man began using his physical advantage to her determent. Now notice what He said to Adam, "Because thou hast harkened to thy wife, and hast eaten of the tree , of which I commanded thee, saying, Thou shalt not eat of it:" The Lord didn't remind the serpent or the woman what He had said, only Adam because Adam was the one He had commanded.
   There is a lesson that is repeated in other places that God ALWAYS holds those to whom he has given instructions responsible for those instructions. Others may be punished for their failure to obey but their disobedience is no excuse for your disobedience. On the other hand if you are faithful to what He has said and they won't hear you, even if they hate you for it, God will never hold you responsible for their disobedience. The Lord curses the ground and tells Adam that he would eat the herb of the field by the sweat of his brow till he returned to dust. The lord then says "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 forever." Let me speculate a little and if i'm wrong don't hold it against me. First of all why was the tree of knowledge in the garden in the first place? If God had not intended man to have knowledge of good and evil, why create the possibility? Perhaps God intended to allow man to mature slowly, perhaps the tree was the first test to see if man would obey. How long had it been since the devil and his angels had rebelled? Of course the Lord knows the end from the beginning and perhaps He knows that many people never really learn until they suffer the consequences of disobedience. As for the tree of life God knew that until man could be changed, for him to live forever with an acute awareness of sin and no power to overcome it would be the worst thing for man so He drove man out of the garden and set an angel to guard it.
God Bless,