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2013. “Marcosian Rituals for Prophecy and Apolytrosis.” Pages 433-448 in Practicing Gnosis. Ritual, Magic, Theurgy and Liturgy in Nag Hammadi, Manichaean and Other Ancient Literature, FS B. A. Pearson. Edited by A. D. DeConick, G. Shaw, and J. D. Turner. Nag Hammadi and Manichaean Studies 85. Leiden: Brill.

2009. “The Star of Judas in the Gospel of Judas.” Pages 326-336 in The Codex Judas Papers: Proceedings of the International Congress on the Tchacos Codex held at Rice University, Houston, Texas. Edited by A. D. DeConick. Nag Hammadi and Manichaean Studies 71. Leiden: Brill.

2005. “The Prayer of Choni in Josephus Jewish Antiquities XIV 24.” Pages 101-116 in Studies in Jewish Prayer. Edited by R. Hayward, B. Embry. Journal of Semitic Studies Supplement 17. Oxford: Oxford University Press.

2005. “Some Observations on Josephus‘ Description of the Essenian Morning Prayer.” Pages 245-253 in Josephus and Jewish History in Flavian Rome and Beyond. Edited by J. Sievers and G. Lembi. Supplements to the Journal for the Study of Judaism 104. Leiden: Brill.

2001. “Mark the Magician and Valentinian Syncretism.” Pages 227-233 in Studia Patristica 35. Papers presented at the Thirteenth International Conference on Patristic Studies held in Oxford 1999, Ascetica, Gnostica, Liturgica, Orientalia. Edited by M. F. Wiles, E. J. Yarnold, and P. M. Parvis. Leuven: Peeters.

2000. “The Exegesis of Homer and Numerology as a Method for Interpreting the Bible in the Writings of Philo of Alexandria.” Pages 91-98 in Jewish Ways of Reading the Bible. Edited by G. J. Brooke. Journal of Semitic Studies Supplement 11. Oxford: Oxford University Press.