The answer is: Eating some fruit

Gen 3:3,6

Ah, the story of the first sin! It all revolves around Adam, Eve, and that infamous fruit. What's fascinating is that the fruit's exact identity is never fully revealed. Over centuries, it has transformed into the universally recognized "forbidden fruit," often depicted as an apple. But if we dig deeper into the original Hebrew text, it's simply referred to as “the fruit of the tree” which symbolizes knowledge and disobedience.

In Genesis 3:6, we witness Eve's choice to eat this fruit, prompted by the elusive serpent—often seen as a representation of temptation. This transaction is pivotal, serving as a metaphor for human free will and the age-old struggle between choice and conscience. You might say it opened Pandora's box, unleashing shame and struggle throughout humanity.

Interestingly, in many ancient cultures, stories of a virgin birth and a perfect garden also imply that the idea of disobedience and temptation is universal. What happened after that first bite teaches a crucial lesson on the nature of consequence: awareness of good and evil came with the knowledge obtained, exponentially complicating the lives of Adam and Eve thereafter.

This unearthed consciousness shifts relationships—not just with God, but also with each other and creation at large. It begs the question of how choices shape our existence—whether in the beauty of a garden or the rough patches of life that follow. This cautionary tale remains dramatic and intensely relatable even today.