The Sermon to the Nephites or Sermon at the Temple says the following:22 But I say unto you, That whosoever is angry with his brother without a cause shall be cin danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.
Notice the difference?22 But I say unto you, that whosoever is angry with his brother shall be in danger of his judgment. And whosoever shall say to his brother, Raca, shall be in danger of the council; and whosoever shall say, Thou fool, shall be in danger of hell fire.
In the KJV is the phrase, "without a cause" while the Book of Mormon version omits that phrase. Interestingly enough, it wasn't until after the death of Joseph Smith that earlier manuscripts of the New Testament were found which also omitted the phrase "without a cause". Most scholars today believe that the phrase, "without a cause" was added later in order to make the teaching less controversial. That also means that it was through Joseph Smith that the world first was introduced to the correct version of this teaching and as a by product this adds legitimacy to the Book of Mormon as an authentic work.
The JST also omits the phrase, by the way.
So, the correct teaching is that we should not get angry at our brother. Now, another important point is that "...the word usually translated as brother is gender neutral in the original Greek, and is more accurately translated as 'brother or sister.'" In short, this scripture is referring to the whole human race. The reason why I point this out is to demonstrate that there is no "wiggle" room is so far as to whom this scripture refers to and what it is asking us to do or not to do.
We are not justified, ever, in being angry at anyone. There is no such thing as "righteous anger". All anger is unrighteous and places us in danger of judgment. This also has implications on parts of the scriptures that talk seemingly talk about God's "anger" or God's "wrath". Clearly God would not command us to not be angry, ever, while He hypocritically is angry and wrathful. Therefore, if we believe God gets angry or is wrathful, then we need to reevaluate our beliefs in light of this.
Now, let us examine the word "Raca" and what is meant by "thou fool" because they are closely related. The word "Raca" is an Aramaic term for contempt. It is also similar in meaning to "apostate". As far as "thou fool" this phrase is not referring to one's intelligence, but rather, this is speaking to "a censorious judging of a man's spiritual and eternal estate" or saying to a person "...thou wicked man, thou ungodly wretch, thou graceless creature..." Indeed the Jews taught that "it is forbidden a man to call his neighbour by a name of reproach, everyone that calls his neighbour (evr) , 'a wicked man', shall be brought down to hell...'
In short, we are not justified, ever, in being angry at anyone, which anger leads to treating others with contempt and finally in our anger to censoriously judge a man's spiritual or eternal estate, calling them a "wicked one". Else we place ourselves in danger of being judged ourselves and eventually even in danger of hell fire, or being "brought down to hell".
The way that we should be instead is that we are to love everyone as ourselves, including also our enemies. We should bless all, do good to all, pray for all, and to show loving kindness and goodness to even those who would use us, abuse us, or who seek to destroy us.
No wonder it takes great faith to keep the commandments of Jesus Christ. The natural man hates the ideas of Christ. The natural man will condemn such things, rebel against such things, and seek to rationalize away the commandments of Jesus Christ. However, as we turn our lives and our wills over the Jesus Christ, it is through His power that we can then keep His commandments and do as He did and become as He was. The natural man can't do these things, doesn't want to become or do such things, but Christ can. So, we should come unto Christ with a broken heart and a contrite spirit and take upon us the name of Christ and be filled with His Spirit so we can be One with Him and with the Father, always abounding in good works.
-Finrock