In the beginnings of Early Christianity we know of only two collections of Christian texts to which the title "New Testament" was given - one from around the middle of the second century, credited to Marcion of Sinope, and the other well known created from around the time of Irenaeus of Lyon towards the end of the same century. For the first time, the new Concordance provides the full Greek list of over 5.500 words and their individual appearances in both these collections in a comparative way. This allows for the discovery of parallels and differences between the collections and their relation. In addition questions of priority, historical, social and theological can be answered, based on their lexicography.