Kittels Theological Dictionary of the New Testament is simply the most in-depth word study tool available. It contains articles on significant theological words in the New Testament, covering their usage in the Old Testament, their secular Greek background, their use in sources such as Josephus, Philo, pseudepigraphal and rabbinical literature, and their use in the New Testament. Where relevant, a subsection on a words use in the Apostolic Fathers is provided. Volume 10 is the index volume and it has indexes for English key words, Greek key words, and scripture references.