Everyone working on Porphyry's Against the Christians refers to the fragment collection compiled by Adolf von Harnack in 1916. Harnack's scholarship was impressive, but his work is difficult to use, and needs revision in the light of new approaches to the collection and interpretation of fragments. This paper draws mainly on the methodological work of Most et al. (1997) to argue that a fragment should not be read apart from its contextual framework. As a case study, this paper examines the Porphyrian fragments that attack the New Testament as preserved by Jerome and concludes that Jerome has his own theological agenda, which influences the way in which he quotes Porphyry. Ultimately, this paper proposes a new fragment collection.