In 3 Nephi 12:22 (an almost verbatim use of Matthew 5:22) Mormons claim Jesus used the word Raca which is from the Greek raká, itself from the Aramaic rêqā, “empty-head, fool, numbskull; good for nothing, worthless man.”

The choice of this word would have completely dumbfounded the Nephites.

To complicate matters further, when revising the King James Bible, Joseph Smith modified the verse to read:

“But I say unto you, that whosoever is angery with his brother, shall be in danger of his judgement; & whosoever shall say to his brother, Raca, or Rabcha, shall be in danger of the Council; and whosoever shall say to his brother, Thou fool, shall be in danger of hell fire.”

Joseph Smith’s New Translation of the Bible – Original Manuscripts (Provo, UT: Religious Studies Center, 2004), 244.

Two important items of note: First, Joseph eliminates “without a cause” here, as he did in the Book of Mormon. In both cases, this is likely due to the advice given by Adam Clarke in 1817 from his landmark Bible Commentary. Second, is the addition of the word “Rabcha,” which is a nonsensical invention of Joseph Smith.