The book starts with Ela, a girl from Parne who suddenly experiences a vision and hears the voice of the Infinite (God). Against her protests that she is too young and a girl, she faces a choice - to accept the role of a prophet (and prophets die young), or to reject it and live a normal, peaceful life. Well, Ela, realising that she cannot live without the Infinite, accepts her calling to be His Prophet, and with her younger sister, goes out to do His will.
I thought that the book was wonderfully written. Plot-wise, it was engrossing, and I couldn't put down my iPad when I started reading it. Because of the fact that all true prophets die young, I was constantly wondering if this encounter with the different royalty would be the encounter that led to her death. This kept the tension of the book fairly high throughout. The plot shows again and again, how important it is to obey the voice of God and to do as He wills. Ela isn't a perfect heroine, and it's through her flaws that we see the mercy of God.
And Ela, I really loved her as a character! Ela has a tender heart, especially for the lost, and is very suited to be a prophet. Yet, she's not a Mary-Sue. In fact, she has quite a temper and tends to question the purpose of the instructions and visions she receives. But as the book progresses, she learns to trust God and grows into her role as a prophet.
Another character is Kien. I think he's meant to counter-balance Ela. In the start, he doesn't believe in God, believing him to be just a God of "Parne". In fact, he tries to use Ela and her visions to help his escape. But as the book progresses, he's touched by the Word and in the end, becomes a believer as well. Kien and Ela do fall in love, but their relationship progressed very naturally.
In conclusion, this is a wonderful book and the start of what I think will be a wonderful series. While there isn't a cliffhanger ending, the ending promises that we will get to see more of Ela and Kien as they grow in their walk with God.