yesterday, today, and forever

KJV has one instance:

8 Jesus Christ the same yesterday, and to day, and for ever.

(Hebrews 13:8)

The Book of Mormon has 7 instances and the D&C has 1, all spelled this way:

same yesterday, today, and forever.

Note: In the 1830 edition, it was always spelled "same yesterday, to-day, and forever."

D&C 

12 Thereby showing that he is the same God yesterday, today, and forever.

(Doctrine and Covenants 20:12)

Why does the Book of Mormon vary from the KJV? 

The KJV had "and to day" but the BofM omits the "and" and spelled it "to-day." KJV had two words, "for ever," but BofM spelled it as one word.

Jonathan Edwards used the phrase over 20 times. He never quoted it exactly from the KJV. He always omitted the "and" before "today, just like the Book of Mormon, and wrote "forever" as one word, not two.

I think, we shall greatly mistake, if we imagine it to be like that absolute independent identity of the First Being, whereby "he is the same yesterday , today , and forever ." 

as he was, infinite ages before the foundations of the world were laid, so he is now and so he will be, with exactly the same glory and happiness uninterrupted, immovable and unchangeable, the same yesterday , today , and forever

'Tis certainly a very strange thing to see him that is from everlasting to everlasting, the same yesterday , today , and forever; immutable, unchangeable, infinite in his essence, so that the whole universe is as nothing to him;

So Christ is the same yesterday , today , and forever (Hebrews 13:8). He is unchangeable in his love to those whom God hath given him. He loved them before the foundation of the world; Jeremiah 31:3,