The Fall: The Serpent Tempts Adam and Eve

God said to Adam," You must not eat fruit from the Tree of Knowledge of Good and Evil. But you may eat the fruit of any other tree in the garden." God saw that it was not good for Adam to be alone in the garden so he made Eve and put her in the garden. One day the serpent lead Eve to the Tree of Knowledge of Good and Evil. He tricked Eve into eating the fruit by telling her that she will surely not die, so she ate the fruit that God told them not to eat. She brought some to Adam and he ate it not knowing where it had come from. They felt ashamed so they hid from God. Even though God all ready knew where they were and what they had done so he asked them where they were to see if they would tell the truth and they had not. 

The consequence for themselves and their descendants is that sin had entered the world..

Original Sin is the tendency to sin innate in all human beings, held to be inherited from Adam in consequence of the Fall.