Isaiah 49:10 (King James Bible) they shall not hunger nor thirst neither shall the heat nor sun smite them
Here the Book of Mormon text repeats the definite article the in the conjunct “the heat nor the sun”, which is characteristic of the Hebrew-like style of the Book of Mormon. (For discussion and examples, see conjunctive repetition in volume 3.) The corresponding King James passage does not repeat the the (“the heat nor sun”). The original Hebrew here has no determiner for either conjunct (literally, “heat and sun”, which occurs within the scope of a preceding negation). Modern English translations treat this conjunct by having the article the for both conjuncts or for neither, thus maintaining some parallelism:
Like the NIV, the Book of Mormon version of Isaiah 49:10 indirectly preserves the parallelism of the original Hebrew.
Summary: Maintain the repeated definite article the in “the heat nor the sun” in 1 Nephi 21:10; the use of the repeated the maintains the parallelism but not the literalness of the Hebrew (which lacks the definite article for both conjuncts).