With the lectionary readings from Mark 1:21-28 and Mark 1:29-39 proclaiming that Jesus cast out demons, Brant Pitre at The Sacred Page highlights this quote from Origen in Against Celsus.
Celsus asserts that it is by the names of certain demons, and by the use of incantations, that the Christians appear to be possessed of (miraculous) power; hinting, I suppose, at the practices of those who expel evil spirits by incantations. And here he manifestly appears to malign the Gospel. For it is not by incantations that Christians seem to prevail (over evil spirits), but by the name of Jesus, accompanied by the announcement of the narratives which relate to Him; for the repetition of these has frequently been the means of driving demons out of men, especially when those who repeated them did so in a sound and genuinely believing spirit.
So, to summarize, in the 3d century CE, Christians exorcists were apparently casting out demons by reading the gospel accounts of Jesus’ exorcisms.
Read the post: Gospel Reading and Early Christian Exorcisms.