Originally Posted By: LukeJavan8
speaking of hocus-pocus: the old Catholic Mass: HOC EST enim
corPUS meum: "this is my body". The priest faced the wall, the
bread became the body of Christ, the uneducated masses (people)
thought it was magic: hence: what they could hear: hocus-pocus.


Quinion advises taking this with "a fair-sized pinch of salt." link