Schaff, Philip. History of the Christian Church (The Complete Eight Volumes in One). Amazon Kindle Edition, 2014.
Volume 2, Ante-Nicene Christianity A.D. 100-325, “Chapter 5. Christian Worship” (Includes an introduction and sections 59-74).
§70. The Celebration of Baptism.
After a brief bibliography about baptism, Schaff describes the rite, referring to the Didache chapter 7 and Justin Martyr, giving extensive quotations (Schaff 2014, Loc. 15383). Schaff goes on to describe the rite without quotations, but based on Tertullian and others.
A candidate for adult baptism would renounce the devil, confess dependence on Christ, and normally agree to the Apostles’ Creed. People were often baptized unclothed, by dipping three times in water (Schaff 2014, Loc. 15393). Pouring also was accepted as needed. A single immersion was accepted later, in the time of Pope Gregory I (Schaff 2014, Loc. 15402). After the baptism itself, there would be a prayer of thanksgiving, another prayer, and a kiss to welcome the baptized person into the community (Schaff 2014, Loc. 15406). An exorcism, rather than a simple renunciation, came to be common after 256 (Schaff 2014, Loc. 154130. Sponsors are mentioned by Tertullian. Schaff associates this with infant baptism and the need to guarantee ongoing Christian training (Schaff 2014, Loc. 15421). Particular days became associated with baptism fairly early, but merely as a matter of symbolic significance.