Christian Mystics
When Christ passed on his knowledge to his disiples he gave them the power to perform the same type of miracles he performed such as healing. The disiples then took on disiples of their own and passed this knowledge down to them. During the course of time this lineage was most likely excomunicated from the church as "heritics" for practicing magic.
Throughout history though many sects and denominations of Christians have relyed on "Mystic" practices, the most prominent perhaps being the Catholic Church in performing exorcisms, though even the practice of baptism could fall under the umberella of mystic practices.