This article aims to assess Anastasius of Sinai’s usage of ancient Chris-tian sources in the Hexaemeron. Close and thorough examination of his quotations from Justin Martyr, Ireneaus of Lyon, Methodius of Olympus and Eustathius of Antioch reveals that, apart from Methodius, the citations have no analogy to any of their works. On the contrary, the cited opinions appear either to have come from different authors, or to have been faked, in toto or in part, by Anastasius. The reason for such a forgery lies in Anastasius’s attempt to rehabilitate the allegorical interpretation of Gen. 1-3, without being accused of Origenism. Anastasius’s witness to the ancient exegetical tradition is proven to be deliberately misleading, and therefore should not be taken at face value.