The Guardian — Jane Hamilton

An exciting, thought-provoking novel of love as steadfast as an angel's, as deep as God's--a passionate story of mercy and forgiveness as great as heaven itself. How is it that Tabris, a special guardian in God's eyes, has come to commit the one unforgiveable crime for guardian angels? And more alarming to the entire celestial world, why did he get away with it?

This book was republished in 2012 under the title The Wrong Enemy, under the author's married name, Jane Lebak. It is available as a Kindle edition and in paperback.