Sin: Entered Into the World by Adam
Source: TTT
Genesis 3:6, 7
When the woman saw that the tree was good for food and pleasing to the eyes, and that it was desirable for obtaining wisdom, she took the fruit and ate it. She also gave some to her husband who was with her, and he ate it. / And the eyes of both of them were opened, and they knew that they were naked; so they sewed together fig leaves and made coverings for themselves.
Romans 5:12
Therefore, just as sin entered the world through one man, and death through sin, so also death was passed on to all men, because all sinned.