According to the law of Exo 21.12-14, if someone killed a person unintentionally, he could flee to the altar for safety. If, however, he killed the person intentionally, he was to be taken from the altar and put to death. Since Joab intentionally murdered these two men, Solomon is acting within the teaching of the Law.

The LORD will bring back his bloody deeds upon his own head: In a footnote Good News Translation provides an alternate translation for the first part of this verse, either “will punish … committed” or “will kill Joab, because he committed those murders.” The meaning is essentially the same in either case. Some other possible renderings are “He will have to take responsibility for those killings and be punished for them” and “the LORD will make him pay for those murders” (Contemporary English Version).

Because … he attacked: Revised Standard Version fails to reflect the word order of the original text when it inserts the words without the knowledge of my father David between these elements. This intervening element, which refers to David’s unawareness of the murders, actually comes in Hebrew after the description of the murders and is more literally “and my father David did not know.” The word because introduces the reason for the punishment that Joab is about to receive. In many languages the original Hebrew order will provide a better model than the usually literal Revised Standard Version; for example, the translation will read something like the following:

• The LORD will punish Joab because he attacked and killed those two men who were more righteous and better than he was. My father David did not know about this matter, but Joab killed Abner, the son of Ner, commander of the army of Israel, and Amasa, the son of Jether, commander of the army of Judah.

Regarding the killing of Abner and Amasa, see the comments on verse 5.

More righteous and better than himself: In some languages it will be necessary to say “who surpassed him in honor and goodness.” In some contexts the two adjectives are distinguished in that the first one has to do with justice and fairness while the second one focuses more on moral goodness. However, several modern translations are content to use a single word (“better” in Good News Translation, Revised English Bible and Contemporary English Version) to convey the idea of the two adjectives in Hebrew.

Quoted with permission from Omanson, Roger L. and Ellington, John E. A Handbook on 1-2 Kings, Volume 1. (UBS Helps for Translators). New York: UBS, 2008. For this and other handbooks for translators see here .