This story is a sequel to The Book of the Arrival

A week after his daughter’s birth and his wife’s death, Argyle Starshine is devastated and exhausted.  His friend Paisley has arrived with a gift to encourage him: a religious text in the same vein as the one Argyle had discovered previously.  Argyle has no desire to read, but Paisley makes him a deal: while Argyle rests, Paisley will read the book to him.

The tale is even older than the one Argyle had found.  Instead of elaborating on the history of the ponies of Maretime Bay, it focuses on the land from which they fled, and one mysterious mare in particular: Twilight Sparkle.

This story is a sequel to The Book of the Arrival

As Equestria recovers from what has been termed the Second Eastern Rebellion, Princess Twilight Sparkle shares the letters written between herself and her rebellious former student.  The Zephyrites, followers of the prophet Warm Zephyr, nearly succeeded in purifying their land of all non-ponies.  Within these letters lies the reason five hundred ponies fled the land of Equestria.  And a question is debated which will define the future of Equestria: what is the true meaning of Friendship?

The manuscript was old, hidden in Maretime Bay's lighthouse for generations at the very least. At first glance, it appears to be a religious text, full of references to unknown places, unknown creatures, unknown rulers. But is there more to the manuscript than meets the eye? Can Maretime Bay's existence really be traced back to a single group of pilgrims seeking a new life? And why would these pilgrims have sought to escape from their princess, Twilight Sparkle?