And renders the Hebrew verbal transition marker that is sometimes translated “And it happened.” See the comments on 2 Kgs 8.3.

When the letter came to them: The letter in this verse is the second letter, the one in which Jehu appeared to ask for the heads of the descendants of Ahab. Some languages may prefer to say “this second letter.” In some languages it will be unnatural to make the letter the subject of the verb came. If this is the case, translators may say “when the leaders of Samaria received the [second] letter.”

They took the king’s sons: It will be noted that Good News Translation replaces the pronoun they with the noun phrase “the leaders of Samaria.” As in verse 4, the decision about how this pronoun is rendered will depend on the textual decision in the first verse of this chapter.

Slew: This archaic English verb is understandably replaced by “killed” in New Revised Standard Version and many other modern versions. On the other hand, New Jerusalem Bible translates “butchered” in an attempt to depict the savagery of the act and reflect the use of a more graphic Hebrew word than the ordinary term for “kill.”

Put their heads in baskets: Revised English Bible says “piled their heads in baskets.” The Hebrew noun translated baskets refers to “baskets” in Jer 24.1 and to cooking pots in 1 Sam 2.14. Either translation is possible here.

Sent them to him; that is, these leaders sent the baskets filled with heads to Jehu. If either or both of the pronouns (them and him) are ambiguous or confusing, a noun or noun phrase may be substituted.

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