The Apostolic Constitutions contains eight treatises on Early Christian discipline, worship, and doctrine, intended to serve as a manual of guidance for the clergy, and to some extent for the laity. It purports to be the work of the Twelve Apostles, whose instructions, whether given by them as individuals or as a body. The summarized structure of the Apostolic Constitutions: Books 1 to 6 are a free re-wording of the Didascalia Apostolorum Book 7 is partially based on the Didache. Chapters 33-45 of book 7 contain prayers similar to Jewish prayers used in synagogues. Book 8 is composed as follows: chapters 1-2 contain an extract of a lost treatise on the charismata chapters 3-46 are based on the Apostolic Tradition, greatly expanded, along with other material chapter 47 is known as the Canons of the Apostles and it had a wider circulation than the rest of the book. The best manuscript has Arian leanings, which are not found in other manuscripts because this material would have been censured as heretical. The Apostolic Constitutions is an important source for the history of the liturgy in the Antiochene rite. It contains an outline of an anaphora in book two, a full anaphora in book seven (which is an expansion of the one found in the Didache), and the complete Liturgy of the eighth book of the Apostolic Constitutions, which is the oldest known form that can be described as a complete divine liturgy.