This verse contains three levels of quotation: the words of Elisha begin in the middle of verse 1; he then quotes the words that the young prophet is supposed to say; and these words in turn include a quotation of what Yahweh says. Many languages will require a simplification of this complex structure. Good News Translation does so by making the words of Yahweh indirect (“… that he anoints you king of Israel”). Another possibility would be to make the words of the young prophet indirect, saying “… and tell him that the LORD is anointing him king over Israel.”
Take the flask of oil, and pour it on his head: The two verbs take and pour may be translated by a single verb in certain languages (so Good News Translation). Others may say something like “use the olive oil to consecrate him by pouring it on his head.”
For Thus says the LORD, see the comments at 1 Kgs 11.31.
I anoint you king over Israel: New Jerusalem Bible uses the perfect tense in English by translating “I have anointed you king over Israel” (similarly Jewish Publication Version), and the Hebrew may be translated this way here, but most modern versions use the present tense as in Revised Standard Version and Good News Translation. For anoint see the comments at 1 Kgs 1.34.
Open the door and flee: In some languages it may be more natural to leave implicit the idea of opening the door (so Good News Translation). The prophet is instructed to run away as quickly as possible after having anointed Jehu as king of Israel.
Do not tarry: The word tarry is rather archaic in English. It is replaced by “linger” in New Revised Standard Version. New International Version has “delay.” This last command is merely a reinforcement in negative terms of the idea contained in the imperative verb flee. In some cases it will be more natural to reverse the order of these two elements and say something like “do not stay there but run away” or “flee for your life” (Revised English Bible).
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 .