When Mrs. Eddy started to explain Christian Science to others, she was faced with the difficulty of having to use existing finite, material terms for the expression of infinite metaphysical ideas. She took great care to select words that most closely represented the spiritual idea she wished to convey. She sometimes prayed for days before the right one came to her thought.
In her writings Mrs. Eddy in some cases explains her choice and use of words, and shows how the common terms she employs are endowed with spiritual meaning in the context of Christian Science. But she could not do this in every case. There is a danger that materially-minded readers might limit her words to their lower meaning, thereby losing the metaphysical message these words are intended to convey.
Though the revelation goes beyond human language, words are necessarily the tools of its communication. So students of Mind-healing need to learn to respect and study the terms Mrs. Eddy so carefully selected. They realize that her scientific terms cannot be replaced by others that may now seem more contemporary without changing her exact meaning.