When Moroni appeared to Joseph Smith, he reworked Mal 4:5-6, making the meaning behind the text much more explicit, such as the role of Elijah and his then-future coming (which would be fulfilled in April 1836 [cf. D&C 110:13-14]). It does not appear to be a textual restoration of the “original” pericope as it appears, without change to the KJV, when it was translated in the Book of Mormon (Jesus quotes Mal 3-4 in 3 Nephi 24-25).
Mal
4:5-6 (KJV) |
3 Nephi
25:5-6 |
D&C
128:17 |
D&C
2:1-3 |
Behold,
I will send you Elijah the prophet before the coming of the great and dreadful day
of the LORD: |
Behold,
I will send you Elijah the prophet before the coming of the great and dreadful
day of the Lord. |
Behold,
I will send you Elijah the prophet before the coming of the great and
dreadful day of the Lord: |
Behold,
I will reveal unto you the Priesthood, by the hand of
Elijah the prophet, before the coming of the great and dreadful day of the
Lord. |
And he
shall turn the heart of the fathers to the children, and the heart of the
children to their fathers, lest I come and smite the earth with a curse. |
And he
shall turn the heart of the fathers to the children and the heart of the
children to their fathers, lest I come and smite the earth with a curse. |
And he
shall turn the heart of the fathers to the children, and the heart of the
children to their fathers, lest I come and smite the earth with a curse. |
And he
shall plant in the
hearts of the children the
promises made to the fathers, and the hearts of the children shall turn to
their fathers. If it were not so, the whole earth would be utterly wasted at
his coming. |
On the coming of Elijah, see, for e.g.:
Refuting the Tanners on the LDS Interpretation of Malachi 4:5-6
New Testament and Early Patristic Expectation of a Future Coming of Elijah