These short introductions to the various Pauline epistles are so called because it is generally believed that they originated in Marcionite circles. They are to be found in some of the manuscripts of the Vulgate. Modern scholarship generally admits Marcionite origin (explains their appearance in the Vulgate as the result of Marcionite teachers at Rome in the second century who translated the Greek epistles of Paul into Latin), although there is some disagreement (cf. M.J. Lagrange, Revue Biblique XXXV , pp. 161-73).