Azrael's Sword

Azrael's Sword is an extremely powerful object in the Physical Plane. Historically, it was once used as a weapon by The Archangel Azrael to take the life of humans when their souls would not come peacefully. Azrael is a cunning swordsman but a skilled negotiator with souls (his preferred method), and as such this kind of thing has not happened since the early days of humanity.

Being stained with so much blood connected to the Physical Plane, Azrael has long since lost the ability to use the sword in the Spiritual Plane anyway. As such it was long ago discarded on Earth.

While Luc was trapped in the Physical Plane, however, he found the old sword and discovered that it had a remarkable trait. From the Physical Plane it can actually take the life of an Angel. Luc shares this knowledge in a book, "Secrets and Mysteries of the Bible" under one of his psudonyms, "Dr. Luc Reagan."