Adam and Eve were vreated in innocence with an ability to sin but waht caused them to need a saviour?
Genesis 2:
16 And the LORD God commanded the man, saying, Of every tree of the garden thou mayest freely eat:
17 But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die.
18 And the LORD God said, It is not good that the man should be alone; I will make him an help meet for him.
Genesis 3:
7 And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together, and made themselves aprons.
8 And they heard the voice of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God amongst the trees of the garden.
9 And the LORD God called unto Adam, and said unto him, Where art thou?
10 And he said, I heard thy voice in the garden, and I was afraid, because I was naked; and I hid myself.
11 And he said, Who told thee that thou wast naked? Hast thou eaten of the tree, whereof I commanded thee that thou shouldest not eat?
They were innocent untilthey ate of the tree of the knowledge of good and evil and thus became accountable. People are not accountable until they obtain the knowledge of good and evil.
Man knew as God knew:
Genesis 3:
21 Unto Adam also and to his wife did the LORD God make coats of skins, and clothed them.
22 And the LORD God said, 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 for ever:
23 Therefore the LORD God sent him forth from the garden of Eden, to till the ground from whence he was taken.
He had knowledge of God's standard and therefore became accountable. That is when one becomes accountable for their sin is when they know as God knows the standard for sin.