Translation: The idea that “charity never faileth” comes from 1 Corinthians 13:8. It is reworked in this passage, however. The concept that one is nothing without charity is repeated, and then the simple statement that “charity never faileth.” Shorn of its context in 1 Corinthians, there is little to go on to understand the function of the phrase in this passage. Only against those unimaginable things that might fail in Paul (prophecies, miracles, knowledge) can we see the importance of the essential nature of this charity.
1 Corinthians 13:8
8 Charity never faileth: but whether there be prophecies, they shall fail; whether there be tongues, they shall cease; whether there be knowledge, it shall vanish away.
None of that is present in this verse. As the translation pulled terminological references from 1 Corinthians 13, this phrase was also part of the borrowed material, but not the context. This tells us that Mormon’s discourse did have a disconnection from the argument in Paul, but the nature of Mormon’s original has been obscured in the process of translation.