New guidelines for religious education in Norfolk suggest expressions such as the Holy Ghost be banned from lessons because they could confuse pupils.
The Norfolk Agreed Syllabus for religious education recommends that teachers use the term Holy Spirit, to avoid comparisons with ghost stories.
Marian Agombar, who compiled the list, said the document provided advice to teachers, but it was not statutory.
The draft rules will be considered by Norfolk County Council this week.
The guidelines also suggest teachers avoid terms such as the "body of Christ" and the "blood of Jesus" because Christians are not actually eating flesh and blood.
In addition, when lecturing on Judaism, teachers are advised not to refer to the first 39 books of the bible as the Old Testament because it suggests the books are out-of-date.
Ms Agombar, said: "We've heard stories of children taking these stories home and becoming confused, particularly the little ones."
The document was a very small part of a large document which provided advice to teachers in the classroom, she added.
"It's basically a list of dos and don'ts for teachers which we have borrowed from someone else and which have already been used to train teachers."
Head of Notre Dame Roman Catholic School in Norfolk, John Pinnington, said: "Updating language generally is good and if it's done with caution and respect it could be a good thing.
"But I'm just concerned about its motives, and if they are to demystify life?
"Life has its mysteries and all religions are part of a mystery based on God. It would be ashame to demystify everything.
"But it all depends on the general context of the document."
Norfolk secretary for the National Union of Teachers, Tony Mulgrew, said: "I'm sure there's a lot of good ideas in this document, but it does all sound a bit silly.
"I've heard that they plan to change the name of the Old Testament because it makes it sound old.
"Will they change the New Testament too, because that's not new is it?
"We probably need to look at the whole document, but it does sound over-the-top."