When the parasite enters the oyster, it seeks to survive on, and destroy, its host.
The oyster responds by secreting an enzyme encasing the parasite.
Layer upon layer, the parasite is coated, until what emerges is a small ball made of a material called nacre. Nacre is also known as mother-of-pearl.
Pearls only exist due to the oyster overcoming risk and adversity.
There is a lesson here on how we can respond to the risk, adversity, and eventual rewards in our own lives.