Every book is a new journey to embark on. I mainly read romances, but I dabble in other genres too.
I found this similar to Mark of the Witch, book 1 of Shayne's The Portal series. They both have a witch and a priest falling in love, reincarnation, and an older priest who is the antagonist and a father like figure to the hero. I still liked Eternity though, maybe more than Mark of the Witch. Witchcraft and reincarnation was more prominent in Eternity, and I liked the idea of immortal witches. This novel also felt a lot more epic due to Nathaniel, the bad guy, being a lot more threatening.