Risto Uro is a Senior Lecturer in New Testament Studies and Chair of the BA programme in Theology and Religious Studies at the University of Helsinki. His research covers such areas as the Synoptic Gospels, the Nag Hammadi Library, and the social history of early Christianity. His publications include Ritual and Christian Beginnings: A Socio-Cognitive Analysis (2016) and Explaining Christian Origins and Early Judaism: Contributions from Cognitive and Social Science (co-edited with Petri Luomanen; 2007). Juliette J. Day is Docent and University Lecturer in Church History in the Faculty of Theology, University of Helsinki, and Senior Research Fellow in Early Christian Liturgy at Blackfriars Hall, University of Oxford. Her research focusses on early Christian liturgy, especially that of Jerusalem/Palestine in late antiquity, and on the interpretation of ancient and contemporary liturgical texts. Her publications include The Baptismal Liturgy of Jerusalem (2007), Reading the Liturgy (2014), Early Roman Liturgy to 600 (co-edited with Marcus Vinzent; 2014), and A Guide to the Study of Liturgy and Worship (co-edited with Benjamin Gordon-Taylor, 2013). Richard E. DeMaris is Senior Research Professor of New Testament Studies at Valparaiso University and has served as the Catholic Biblical Association Visiting Professor to the Pontifical Biblical Institute in Rome. He is a research associate of the Nordic Project on Ritual and the Emergence of Early Christian Religion and was a staff member of the Ohio State University Excavations at Isthmia, Greece, in the 1990s. His publications on ritual include Early Christian Ritual Life (co-edited with Jason Lamoreaux and Steven Muir 2018), and The New Testament in Its Ritual World (2008). Rikard Roitto is Docent and University Lecturer of Biblical Studies, New Testament, at Stockholm School of Theology. In his research, he integrates historical-critical methods with social, psychological and cognitive sciences to understand early Christian texts and communities. His research interests include social identity, norms, rituals of penance and forgiveness, conflict resolution, and baptism in early Christianity. He has written several articles on ritual practices of reproof, repentance, penance, intercession for forgiveness and reintegration of deviant group members in early Christianity.