• Formative Christianity
• Gnosticism
• Religions of Antiquity
• Formative Islam
• Comparative History of Religions

My main area of research over the years has been Valentinianism, the most important variety of Christian ‘Gnosticism’ in Antiquity. I regard it as a distinct branch of Christianity, founded by Valentinus c. 150 CE and still alive at the end of the fourth century. The Valentinians were condemned as heretics by the theologians of mainstream Christianity.

I have worked extensively on the Coptic manuscripts from Nag Hammadi, which among other things contain several important Valentinian texts, and I am co-editor of the book series Nag Hammadi and Manichaean Studies.

Greco-Roman religion and the history of early Christianity are general research interests that cohere naturally with my specialised research.

Another research interest is Islam, where I have previously worked, among other things, on Sufism. I currently take a special interest in the origins of the Qur’an and its Late Antique context.

Finally I have always taken an interest in comparative issues in the study of religion, both thematic and historical. In this area I am now looking at macro-historical processes in the light of cognitive psychology and the general theory of evolution.

 

Lecture

• Einar Thomassen (2018). Islam, kristendom og jødedom: Har de den samme gud?. (external link)
• Einar Thomassen (2015). Barn født utenfor ekteskap i ulike religioner. (external link)
• Einar Thomassen (1996). "Islam og menneskerettighetene.". (external link)
• Einar Thomassen (1993). Filologi og hermeneutikk. (external link)
• Einar Thomassen (2017). The Reformation and its role in the world history of religions. (external link)
• Einar Thomassen (1996). "Hvordan myte blir rite.". (external link)
• Einar Thomassen (2002). “Hva er Thomasevangeliet?”. (external link)
• Einar Thomassen (2000). Rettroende og kjettere blant Romas kristne i det andre århundret. (external link)
• Einar Thomassen (1993). Valentin som religionsstifter. (external link)
• Einar Thomassen (1993). Le valentinisme #`a Nag Hammadi. (external link)
• Einar Thomassen (1996). Innføring i Islam. (external link)
• Einar Thomassen (2001). Zeus and Athena in the Myths of the Gnostics. (external link)
• Einar Thomassen (2017). Hellig krig i Koranen og Islam. (external link)
• Einar Thomassen (2005). The Paternal Womb: Valentinian and Neopythagorean ideas about first beginnings. (external link)
• Einar Thomassen (1993). Forskning om gnostisismen i Norden. (external link)
• Einar Thomassen (2007). Den kristne kanon: Hvordan ble Det nye testamente satt sammen?. (external link)
• Einar Thomassen (2006). Hvordan Bibelen ble til. (external link)
• Einar Thomassen (2018). Comparing Religions, Comparing Monotheisms. (external link)
• Einar Thomassen (2015). Apokryfe juleevangelier. (external link)
• Einar Thomassen (1993). The Derivation of Matter in Monistic Gnosticism. (external link)
• Einar Thomassen (1996). "Gnostikerne og den tidlige kristendommens historie.". (external link)
• Einar Thomassen (1996). "Mosk"/erommet". (external link)
• Einar Thomassen (2015). Jihad – krig på Guds vei i Koranen og Islam. (external link)
• Einar Thomassen (1996). Islam som fiendebilde. (external link)
• Einar Thomassen (1996). "Innføring i Islam.". (external link)
• Einar Thomassen (1996). "Det nye kristendomsfaget.". (external link)
• Einar Thomassen (1993). Ortodoksi og heterodoksi i det andre århundrets Roma. (external link)
• Einar Thomassen (1996). "Sigmund Mowinckel: An Insider's View.". (external link)
• Einar Thomassen (2014). Forskjeller mellom kristendommen og islam. (external link)

Academic book chapter

• Einar Thomassen (2000). Wilhelm Schencke—Norway’s First Professor in History of Religions. (external link)
• Einar Thomassen (1995). Notes pour la d#/elimitation d'un corpus valentinien #`a Nag Hammadi. (external link)
• Einar Thomassen; Louis Painchaud (2007). Interprétation de la gnose (NH XI, 1). (external link)
• Einar Thomassen (2017). Gnosis and Philosophy in Competition. (external link)
• Einar Thomassen (2019). There Is No Such Thing as Gnosticism: But What Have We Got Instead?. (external link)
• Einar Thomassen (2009). Jesus in the New Testament Apocrypha. (external link)
• Einar Thomassen (2012). Egypt som paradiset. (external link)
• Einar Thomassen (2018). Mani und der Manichäismus. (external link)
• Einar Thomassen (2018). Sethianismus. (external link)
• Einar Thomassen (2021). Was there a distinct Gnostic Book Culture?. (external link)
• Einar Thomassen (1996). "Welcoming a New Department". (external link)
• Einar Thomassen (2010). Le valentinisme à Nag Hammadi. (external link)
• Einar Thomassen (2018). The rhetorical construction of heresy in the Church Fathers. (external link)
• Einar Thomassen (1999). "Is Magic a Subclass of Ritual?". (external link)
• Einar Thomassen (2006). Hva enhver student i religionsvitenskap trnger å vite om filologi. (external link)
• Einar Thomassen (2013). Sethian Names in Magical Texts: Protophanes and Meirotheos. (external link)
• Einar Thomassen (2004). Musings on 'Syncretism'. (external link)
• Einar Thomassen (2007). Tekstkritikk og kanon. (external link)
• Einar Thomassen (2007). From Wisdom to Gnosis. (external link)
• Einar Thomassen; Louis Painchaud (2007). Traité tripartite (NH I, 5). (external link)
• Einar Thomassen (2008). Kjetteri i middelalderen: katarene. (external link)
• Einar Thomassen (2008). Kjetteribegrepets opprinnelse og de første kjetterne. (external link)
• Einar Thomassen (1993). The Platonic and the Gnostic "Demiurge". (external link)
• Einar Thomassen (2019). Valentinus and the Valentinians. (external link)
• Einar Thomassen (2007). The Interpretation of Knowledge. (external link)
• Einar Thomassen (2013). The Valentinian Materials in James (NHC V,3 and CT,2). (external link)
• Einar Thomassen (2002). "Jesu hemmelige ord: Thomasevangeliet og andre apokryfe evangelier". (external link)
• Einar Thomassen (2018). Mani und der Manichäismus. (external link)
• Einar Thomassen (2018). Sethianismus. (external link)
• Einar Thomassen (2021). Was there a distinct Gnostic Book Culture?. (external link)
• Einar Thomassen (2018). Saving Letter, Saving Book: The Hymn of the Pearl, the 23rd Ode of Solomon and the Gospel of Truth. (external link)
• Einar Thomassen (2001). Et gnostisk syn på oppstandelsen. (external link)
• Einar Thomassen (2013). Going to Church With the Valentinians. (external link)
• Einar Thomassen (2015). Filologiens videnskabelighet. (external link)
• Einar Thomassen (2008). Kilder og arbejdsredskaper til studiet af gnosticismen. (external link)
• Einar Thomassen (2008). Judasevangeliet og gnosticismen. (external link)
• Einar Thomassen (2007). “Forgery” in the New Testament. (external link)
• Einar Thomassen (2011). Baptism among the Valentinians. (external link)
• Einar Thomassen (2007). The Valentinian School of Gnostic Thought. (external link)
• Einar Thomassen (2007). Forord. (external link)
• Einar Thomassen (2018). A ‘Sayings Gospel’ attested at Nag Hammadi. (external link)
• Einar Thomassen (2006). The Reception of Greco-Roman Religious and Cultic Terminology in Judaism and Christianity, with Special Reference to Sacrificial Terminology. (external link)
• Einar Thomassen (2018). Basileides und seine Anhänger. (external link)
• Einar Thomassen; Tarald Rasmussen (1999). Humanismen. (external link)
• Einar Thomassen (2021). Widengren, Gnosticism, and the Religionsgeschichtliche Schule. (external link)
• Einar Thomassen (2003). Becoming a different person: Baptism as an initiation ritual. (external link)
• Einar Thomassen (2003). Das norwegische Experiment mit Religionsunterricht für alle. (external link)
• Einar Thomassen (1999). "Is Philology Relevant?". (external link)
• Einar Thomassen (1995). Logos apo siges proelthon (Ignatius, Mag. 8:2). (external link)
• Einar Thomassen (2013). Ikke bare Bibelen: Hellige skrifter i antikken. (external link)
• Einar Thomassen (2013). Saved by nature? The question of human races and soteriological determinism in Valentinianism. (external link)
• Einar Thomassen (2000). The Derivation of Matter in Monistic Gnosticism. (external link)
• Einar Thomassen (2009). Valentinian ideas about salvation as transformation. (external link)
• Einar Thomassen (2007). IV. Les écrits valentiniens de Nag Hammadi. (external link)
• Einar Thomassen (2007). Den gnostiske reisen. (external link)
• Rex Seán OFahey; Einar Thomassen (1993). Letters to Makkib, Abd al-Aziz. (external link)
• Einar Thomassen (2018). Temple and Sacerdotal Imagery in Valentinian Gnosticism. (external link)
• Einar Thomassen (2007). The Treatise on Resurrection. (external link)
• Einar Thomassen (2010). Heracleon. (external link)
• Einar Thomassen (2016). What Is a “God” Actually?: Some Comparative Reflections. (external link)
• Einar Thomassen (1997). How Valentinian is The Gospel of Philip?. (external link)
• Einar Thomassen (2025). Manichaeans and Gnostics on the Creation of Humanity. (external link)
• Einar Thomassen (1999). Islam. (external link)
• Einar Thomassen (2009). Dialogues with the Archons: The Post-mortem Encounters of the Ascending Soul in Gnostic Texts. (external link)
• Einar Thomassen (1995). Ortodoksi og heterodoksi i det andre århundrets Roma. (external link)
• Einar Thomassen (2008). Is Judas really the Hero of the Gospel of Judas?. (external link)
• Einar Thomassen (2017). The Melothesia of the Apocryphon of John and the Umm al-kitāb. (external link)
• Einar Thomassen; Anne Pasquier (2007). L’Évangile de la vérité (NH I, 3; XII, 2). (external link)
• Einar Thomassen (2011). Philology. (external link)
• Einar Thomassen; Alin Suciu (2011). An Unknown ‘Apocryphal’ Text from the White Monastery. (external link)
• Einar Thomassen (2012). What is Heresy, and Why Did it Matter?. (external link)
• Einar Thomassen (2007). The Gospel of Truth. (external link)
• Einar Thomassen (2007). The Tripartite Tractate. (external link)
• Einar Thomassen (2010). Some Notes on the Development of Christian Ideas about a Canon. (external link)
• Einar Thomassen (2010). Orphics and Gnostics. (external link)
• Einar Thomassen (2006). Religious Education in a Pluralistic Society: Experiences from Norway. (external link)
• Einar Thomassen (2006). Gos. Philip 67:27–30: not “in a mystery”. (external link)
• Einar Thomassen (2018). Bardesanes (Bardaisan) von Edessa. (external link)
• Einar Thomassen (2021). Philology. (external link)
• Einar Thomassen (1998). Moskérommet. (external link)

Conference lecture

• Einar Thomassen (2018). Was there a special Gnostic book culture?. (external link)
• Einar Thomassen (2015). There is no such thing as Gnosticism. But what have we got instead?. (external link)
• Einar Thomassen (2005). Tekstkritikk og kanon. (external link)
• Einar Thomassen (2003). An Unknown Sayings Gospel. (external link)
• Einar Thomassen (2017). Protology and Eschatology in Gnostic Thought. (external link)
• Einar Thomassen (1997). Is Philology Relevant?. (external link)
• Einar Thomassen (2013). The World of Symbols in Valentinian Gnosticism. (external link)
• Einar Thomassen (2017). Religion among the Societal Challenges: Opportunities for Research on Religion in the Third Pillar of Horizon 2020. (external link)
• Einar Thomassen (2017). Historien om opprettelsen av religionsvitenskap ved UiB. (external link)
• Einar Thomassen (2017). Canonization and Codification. (external link)
• Einar Thomassen (2017). Orphism as a Religion. (external link)
• Einar Thomassen (2006). Valentinianism: A misunderstood chapter in the history of early Christianity. (external link)
• Einar Thomassen (2000). Orthodoxy and Heresy in Second Century Rome. (external link)
• Einar Thomassen (2000). Early Christian Initiation and the Theory of Transformation Rituals. (external link)
• Einar Thomassen (2002). "Who were the Valentinians?". (external link)
• Einar Thomassen (2002). "Presentasjon av høringsutkastet til ny KRL-plan". (external link)
• Einar Thomassen (2013). The Relative Chronology of the Valentinian Systems. (external link)
• Einar Thomassen (2015). Were there Valentinian Schools?. (external link)
• Einar Thomassen (2007). Islamic Hell. (external link)
• Einar Thomassen (2015). The Emergence of Islam. (external link)
• E Ulvestad; A Kanestrøm; TM Madland et al. (2000). Evaluation of diagnostic tests for antinuclear antibodies in rheumatological practice. (external link)
• Einar Thomassen (2006). The Spiritual Seed: Response. (external link)
• Einar Thomassen (2000). Ancient Christian Baptism as an Initiation Rite. (external link)
• Einar Thomassen (2002). "Who were the Valentinians?". (external link)
• Einar Thomassen (2002). "Presentasjon av høringsutkastet til ny KRL-plan". (external link)
• Einar Thomassen (2013). The Relative Chronology of the Valentinian Systems. (external link)
• Einar Thomassen (2007). Valentinian ideas about salvation as transformation. (external link)
• Einar Thomassen (2007). La semence spirituelle. (external link)
• Einar Thomassen (2013). The Rhetorical Construction of Heresy in the Church Fathers. (external link)
• Einar Thomassen (2003). Marcus the Gnostic and female prophetesses. (external link)
• Einar Thomassen (2017). Asceticism at the Threshold between Christianity and Formative Islam. (external link)
• Einar Thomassen (2017). Eusebius on Apollonius: Recasting the boundaries of religion, magic and philosophy (Reply to Hierocles).. (external link)
• Einar Thomassen (2006). Religionsfrihetens grenser i antikken. (external link)
• Einar Thomassen (2005). Gnostic Hell. (external link)
• Einar Thomassen (2006). The Invention of Heresy. (external link)
• Einar Thomassen (2000). Orthodoxie et hérésie à Rome au deuxième siècle. (external link)
• Einar Thomassen (2001). Muhammad i skolen. (external link)
• Einar Thomassen (2002). "Revelation as Book and Book as Revelation: Reflections on the Gospel of Truth.”. (external link)
• Einar Thomassen (2002). Valentinianismen. (external link)
• Einar Thomassen (2005). Functions of scripture in ancient Christianity. (external link)
• Einar Thomassen (2005). Imagistic and doctrinal dimensions of Christian Gnostic ritual. (external link)
• Einar Thomassen (2013). Were Gnostics Over-achievers?. (external link)
• Einar Thomassen (2015). Theological and Philosophical Treatises in the Nag Hammadi Codices. (external link)
• Einar Thomassen (2015). The Axial Age and the Question of Islam. (external link)
• Einar Thomassen (2007). From life cycle rituals to rituals of initiation. (external link)
• Einar Thomassen (2003). Globalisation in Antiquity: Response. (external link)
• Einar Thomassen (2003). From Wisdom to Gnosis. (external link)
• Einar Thomassen (2005). The Reception of Graeco-Roman Religious and Cultic Terminology in Judaism and Christianity with a Special Reference to Sacrificial Terminology. (external link)
• Einar Thomassen (2006). Valentiniansk kristologi og soteriologi - et misforstått kapitel i kirkehistorien. (external link)
• Einar Thomassen (2006). 1 Mos 1:26-27: den religionshistoriske bakgrunnen. (external link)
• Einar Thomassen (2013). "Saved by Nature": Searching for the Right Questions. (external link)
• Einar Thomassen (1999). Is Magic a Subclass of Ritual?. (external link)
• Einar Thomassen (2017). Response to Geoff Smith, “Anti-Origenist Redaction in the Fragments of the Gospel of Truth (NHC XII,2).”. (external link)
• Einar Thomassen (2006). Is Judas really the hero of the Gospel of Judas?. (external link)
• Einar Thomassen (2000). Early Christian Initiation: The Valentinian Version. (external link)
• Einar Thomassen (2000). Orthodoxy and Heresy in Second Century Rome. (external link)
• Einar Thomassen (2001). The epiphany of gnosis. (external link)
• Einar Thomassen (2002). "Thomasevangeliet og andre apokryfe evangelier". (external link)

Popular science article

• Einar Thomassen (2008). The Gospel of Judas, or, Is Philology a Science?. (external link)
• Einar Thomassen (2004). Dualisme på godt og ondt. (external link)
• Einar Thomassen (2017). 50 år med religionsvitenskap i Bergen. (external link)
• Einar Thomassen (2020). Da julen ble til. (external link)

Journal review

• Einar Thomassen (2015). Anmeldelse av Kristin Brandtsegg Johansen, Maria Magdalena: Disippelen Jesus elsket. (external link)
• Einar Thomassen (2022). Review of Joseph Verheyden, Jens Schröter, and Tobias Nicklas (ed.), Texts in Context: Essays on Dating and Contextualising Christian Writings from the Second and Early Third Centuries (Bibliotheca Ephemeridum Theologicarum Lovaniensium 319; Peeters; 2021). (external link)
• Einar Thomassen (2020). Anmeldelse av Bjørn Are Davidsen, Lurt av læreboken? Feil og forvirring om kristen tro i læremidlene.. (external link)
• Einar Thomassen (2002). Moskeer i Norge. (external link)
• Einar Thomassen (2010). Anmeldelse av Barbara Aland, Was ist Gnosis?. (external link)
• Einar Thomassen (2011). Anmeldelse av Uwe-Karsten Plisch, Das Thomasevangelium. Originaltext mit Kommentar (Stuttgart 2007). (external link)
• Einar Thomassen (2022). Sarah-Magdalena Kingreen, Tertullians Schrift Adversus Valentinianos. (external link)
• Einar Thomassen (2010). Anmeldelse av Barbara Aland, Was ist Gnosis?. (external link)
• Michael Stausberg; Einar Thomassen; Clemens Cavallin et al. (2008). Anmeldelse Arne Bugge Amundsen (red.), Norges religionshistorie, Universitetsforlaget, Oslo, 2005. (external link)
• Einar Thomassen (2011). Anmeldelse av M. Ziegler, Successio. Die Vorsteher der stadrömischen Christengemeinde in den ersten beiden Jahrhunderten. (external link)
• Einar Thomassen (2018). The Qur’an: A New Annotated Translation. By Arthur J. Droge.. (external link)
• Einar Thomassen (2010). Anmeldelse av Anders-Christian Jacobsen (ed.), The Discursive Fight over Religious Texts in Antiquity. (external link)
• Einar Thomassen (2014). Anmeldelse av Bart D. Ehrman, Forgery and Counterforgery. (external link)
• Einar Thomassen (2019). Review of Exposé du mythe valentinien et textes liturgiques (NH XI,2). By Wolf-Peter Funk and Jean-Pierre Mahé. Québec/Louvain 2016.. (external link)
• Einar Thomassen (2010). Anmeldelse av Ismo Dunderberg, Beyond Gnosticism: Myth, Lifestyle, and Society in the School of Valentinus. (external link)
• Einar Thomassen (2013). Anmeldelse av Jan N. Bremmer, The Rise of Christianity through the Eyes of Gibbon, Harnack and Rodney Stark. (external link)

Book anthology

• Einar Thomassen (2010). Canon and Canonicity: The Formation and Use of Scripture. (external link)
• Anders Klostergaard Petersen; Jesper Hyldahl; Einar Thomassen (2008). Mellem venner og fjender : en folkebog om Judasevangeliet, tidlig kristendom og gnosis. (external link)
• Anders Klostergaard Petersen; Jesper Hyldahl; Einar Thomassen (2008). Mellem venner og fjender : en folkebog om Judasevangeliet, tidlig kristendom og gnosis. (external link)
• Christoph Markschies; Einar Thomassen (2020). Valentinianism: New Studies. (external link)

Academic article

• Einar Thomassen (2017). The Eucharist in Valentinianism. (external link)
• Einar Thomassen (2018). To profeter. (external link)
• Einar Thomassen (1994). Exodus 1-15, exempelvis. (external link)
• Einar Thomassen (2021). Gnostic Prophecy: The Case of Marcus the Magician and his Women. (external link)
• Einar Thomassen (1992). Målestokken og spanskrøret: Kanon som religionsvitenskapelig term. (external link)
• Einar Thomassen (2016). Gnostic Paradises. (external link)
• Einar Thomassen (1994). Gnostic Semiotics: The Valentinian Notion of the Name. (external link)
• Einar Thomassen (1994). J. Zandee: The Teachings of Sylvanus. (external link)
• Einar Thomassen (1998). Religionsvitenskap i skolen?. (external link)
• Einar Thomassen (2004). Anmeldelse av P. Mirecki og M. Meyer (utg.), Magic and Ritual in the Ancient World. (external link)
• Einar Thomassen (1995). Spiseritualer blant de første kristne. (external link)
• Einar Thomassen (2021). Gnostic Prophecy: The Case of Marcus the Magician and his Women. (external link)
• Einar Thomassen (1997). Satansversene: Fiksjon og fakta. (external link)
• Einar Thomassen (2019). Da religionsvitenskapen kom til Bergen. (external link)
• Einar Thomassen (2020). Were There Valentinian Schools?. (external link)
• Einar Thomassen (2017). Theological and Philosophical Treatises in the Nag Hammadi Codices. (external link)
• Einar Thomassen (2010). Le valentinisme à Nag Hammadi. (external link)
• Einar Thomassen (1998). Teologi og religionshistorie�mot en ny tverrfaglig identitet?. (external link)
• Einar Thomassen (2004). Orthodoxy and Heresy in Second Century Rome. (external link)
• Einar Thomassen (2009). Islamic Hell. (external link)
• Einar Thomassen (2025). A Source-Critical Translation of the Apocryphon of John (Short Recension). (external link)
• Einar Thomassen (1993). Gnostic Semiotics: The Valentinian Notion of the Name. (external link)
• Einar Thomassen (2022). Protology and Eschatology in Gnostic Thought. (external link)
• Einar Thomassen; Alexandros Tsakos; Christian Hervik Bull et al. (2013). A New Edition of the Wizz Codex with an English Translation. (external link)
• Einar Thomassen (2013). Guder og andre overmenneskelige aktører. (external link)
• Einar Thomassen (2004). The Epiphany of Gnosis. (external link)
• Einar Thomassen (2004). Anmeldelse av Ennio Sanzi, I culti orientali nell'impero romano: Un'antologia di fonti. (external link)
• Einar Thomassen (2011). Minnetale over professor Alv Kragerud. (external link)
• Einar Thomassen (2011). Jakten på gnostiske egg. (external link)
• Einar Thomassen (2020). The Relative Chronology of the Valentinian Systems. (external link)
• Einar Thomassen (1995). L´historie du valentinisme et le Trait#/e tripartite. (external link)

Encyclopedia entry

• Einar Thomassen (2022). Nag Hammadi. (external link)
• Einar Thomassen (2016). Holy Book of the Invisible Spirit, The (NHC III,2; IV,2). (external link)
• Einar Thomassen (2020). Melchizedek (NHC IX,1). (external link)
• Einar Thomassen (2011). Authoritative Teaching (NHC VI,3). (external link)
• Einar Thomassen (2009). Allogenes (NHC XI,3). (external link)
• Einar Thomassen (2012). Concept of Our Great Power (NHC VI,4). (external link)
• Einar Thomassen (2016). Hypsiphrone (NHC XI, 4). (external link)
• Einar Thomassen (2009). Archon/Archons. II. Christianity. (external link)
• Einar Thomassen (2016). Bridal Chamber. (external link)
• Einar Thomassen (2016). Sophia. (external link)
• Einar Thomassen (2015). Gnosis, Gnosticism, II Gnosis and New Testament. (external link)
• Einar Thomassen (2011). Barbelo-Gnostics. (external link)
• Einar Thomassen (2009). Adam, The Apocalypse of (NHC V,5). (external link)
• Einar Thomassen (2016). Interpretation of Knowledge, The (NHC XI,1). (external link)
• Einar Thomassen (2009). Asclepius (NHC VI,8. (external link)
• Einar Thomassen (2019). Marsanes (NHC X,1). (external link)
• Einar Thomassen (2016). Johannine Literature. (external link)
• Einar Thomassen (2015). Gnosis, Gnosticism, VI.A Patristic and Orthodox Churches. (external link)
• Einar Thomassen (2015). Gospel of Truth, The (NHC I,3; XII,2). (external link)
• Einar Thomassen (2013). Discourse on the Eighth and Ninth, The (NHC VI,6). (external link)

Non-fiction monograph

• Einar Thomassen (2011). Manikeiske skrifter. Utvalg og innledende essay av Einar Thomassen; oversatt av Prods Oktor Skjærvø og Einar Thomassen. (external link)
• Einar Thomassen; Tarald Rasmussen (1999). Kildesamling til Kristendomskunnskap med religions- og livssynsorientering. (external link)
• Einar Thomassen; Halvor Moxnes (2001). Apokryfe evangelier. (external link)
• Einar Thomassen; Bernd Radtke; Radtke Bernd (1993). The Letters of Ahmad Ibn Idris. Edited, translated and annotated by Albrecht Hofheinz, Ali Salih Karrar, R.S. 0Fahey, Bernd Radtke and Einar Thomassen. (external link)
• Einar Thomassen (2003). Mircea Eliade: Det hellige og det profane, og andre skrifter. (external link)
• Einar Thomassen; Tarald Rasmussen (1999). Kildesamling til kristendomskunnskap med religions- og livssynsorientering: Tilleggshefte. (external link)
• Einar Thomassen; Anne Ingvild S Gilhus (2002). Gnostiske skrifter. (external link)
• Einar Thomassen; Bernd Radtke (1993). The Letters of Ahmad ibn Idris. (external link)
• Tarald Rasmussen; Einar Thomassen (1999). Kildesamling til Kristendomskunnskap med religions- og livssynsorientering; Tilleggshefte. (external link)
• David R. Jordan; Hugo Montgomery; Einar Thomassen (1999). The world of ancient magic: Papers from the first International Samson Eitrem Seminar at the Norwegian Institute at Athens 4-8 May 1997. (Papers from the Norwegian Institute at Athens 4). (external link)

Academic commentary

• Einar Thomassen; Louis Painchaud; Wolf-Peter Funk (2010). L’Interprétation de la gnose (NH XI,1). (external link)

Master’s thesis

• Einar Thomassen; Helge Line Aasland (2007). Konstruksjon av tawhid i politisk islamsk diskurs. (external link)
• Einar Thomassen; Helge Line Aasland (2007). Konstruksjon av tawhid i politisk islamsk diskurs. (external link)
• Einar Thomassen; Marius Rognstad (2007). Gnostiske initiasjonsritualer: En studie av initiasjonsritualene i 2. Jesubok i Codex Brucianus. (external link)

Academic monograph

• Einar Thomassen (2021). The Coherence of “Gnosticism”. (external link)
• Einar Thomassen (2021). The Coherence of “Gnosticism”. (external link)
• Einar Thomassen (2006). The spiritual seed : the church of the "Valentinians". (external link)
• Einar Thomassen (2023). Before Valentinus: The Gnostics of Irenaeus. (external link)

Academic literature review

• Einar Thomassen (2014). Are gods really moral monitors? Some comments on Ara Norenzayan’s Big Gods by a historian of religions. (external link)
• Einar Thomassen (2015). (Review of) J. Rüpke (ed.),The Individual in the Religions of the Ancient Mediterranean. (external link)
• Einar Thomassen (2010). Anmeldelse av Johanna Brankaer/Hans-Gebhadt Bethge, Codex Tchacos: Texte und Analysen. ISBN 978-3-11-019570-5. (external link)

Media feature article

• Einar Thomassen (2004). Om skaut og 'islam'. (external link)
• Einar Thomassen (1993). Omtale av J. Zandee, The Teachings of Sylvanus. (external link)
• Einar Thomassen (1996). Anmeldelse av S. Richter, Exegetisch-literarkritische Untersuchungen von Herakleidespsalmen des koptisch-manichäischen Psalmenbuches. (external link)
• Einar Thomassen (1997). Det misforståtte faget. (external link)
• Einar Thomassen (1996). Anmeldelse av A. Khosroyev, Die Bibliothek von Nag Hammadi: Einige Probleme des Christentums in Ägypten während der ersten Jahrhunderte. (external link)
• Peder Gravem; Sverre Dag Mogstad; Tarald Rasmussen et al. (2001). Fellesfag i forandring. (external link)
• Einar Thomassen (2007). Tidsskriftartikkelfetisjismen. (external link)
• Einar Thomassen (1996). "Det nye religiøse Norge.". (external link)
• Einar Thomassen (1996). Fire innlegg om religionsvitenskapens fremtid: Innledning. (external link)
• Einar Thomassen (1998). Anmeldelse av G. Wurst, Die Bema-Psalmen. (external link)

Professional article

• Einar Thomassen (2017). Selektiv historieskrivning. (external link)

Textbook

• Einar Thomassen (2023). Jødedom, kristendom, islam: Sammenligninger. (external link)
• Einar Thomassen; Tarald Rasmussen (2002). Kristendommen: En historisk innføring. (external link)
• Einar Thomassen; Tarald Rasmussen (2007). Kristendomen : en historisk introduktion. (external link)
• Einar Thomassen; Tarald Rasmussen (2000). Kristendommen: En historisk innføring. (external link)
• Ingvild Sælid Gilhus; Einar Thomassen (2010). Oldtidens religioner. Midtøstens og Middelhavsområdets religioner. (external link)

Research report

• Einar Thomassen (1994). Islam. (external link)
• Einar Thomassen; David R. Jordan; Hugo Montgomery (1999). The world of ancient magic: Papers from the first International Samson Eitrem Seminar at the Norwegian Institute at Athens 4-8 May 1997. (Papers from the Norwegian Institute at Athens. (external link)

Radio or TV participation

• Einar Thomassen (2017). Om nyere Koran-forskning. (external link)
• Einar Thomassen (2015). Nyoppdaget Koran-håndskrift i Birmingham. (external link)
• Einar Thomassen (2002). Kristendommen i den antikke verden. (external link)

Introduction

• Christoph Markschies; Einar Thomassen (2020). Introduction. (external link)

Editorial/Leader article

• Einar Thomassen (2009). The uses of hell. (external link)

Media interview

• Einar Thomassen; Marika Muhonen Nilsen (2002). Nordisk nysgjerrighet i Alexandria. (external link)

Working paper

• Richard Natvig; Randi Brochmann; Dominique Dao-Vu et al. (1998). Studiehefte: Studierettleiing for fjernundervisningsstudentar i Religionsvitskap delfag. Modul 1. (external link)

See a complete overview of publications in NVA.

• The coherence of ‘Gnosticism’
• Comparative themes of Judaism, Christianity, and Islam (textbook)
• The Study of Religion (short introduction)
• Topics of formative Islam
• The two versions of the Gospel of Truth