Josiah kept the passover to his Lord in Jerusalem: Josiah ruled in Judah from 640 to 609 B.C. In many languages it will be helpful to identify Josiah as “King Josiah” (Good News Bible). The passover is the annual celebration held by Jews to remember the events surrounding their escape from slavery in Egypt, led by Moses. It centers around a meal (see Exo 12.43—13.10; Deut 16.1-8). The Hebrew word for passover is derived from the verb meaning “to pass over,” which is used in Exo 12 (verses 12, 23, 27)as, where it says that the angel of the LORD “passed over” the homes of the Hebrews during the night when he destroyed the firstborn sons of the Egyptians. Translators who do not already have a good expression for passover may call it “festival [or, fiesta] of deliverance” or “festival of passing over.” The phrase to his Lord may be rendered “in honor of the Lord” (Good News Bible). However, some translators may need to say “in honor of the heavenly ruler” or even “in honor of God” if Lord will be misunderstood as a human ruler. Lord (Greek kurios) is the equivalent of the Hebrew ʾadonai meaning “One who rules” or “Master.” For this whole clause the Contemporary English Version (Contemporary English Version) has “Josiah commanded that Passover be celebrated in Jerusalem to honor the Lord.” This helpful model indicates that Josiah did not celebrate the Passover alone.
He killed the passover lamb: The passover lamb was the animal slaughtered to be served at the Passover meal. The passover lamb is literally “the Passover” (An American Translation). Revised Standard Version supplies the implied information of lamb. But Good News Bible uses the plural “animals,” since more than one lamb was killed here and the animals killed for the Passover meal could be either male sheep or male goats (see 1 Esdras 1.7), but only those that were a year old (see Exo 12.5). He killed does not mean that King Josiah himself killed the animals, only that it was done at his direction. The Levites actually killed them (see verse 6). Good News Bible does not misrepresent the Greek text by saying “they killed the animals for the festival,” so it may be used as a model. Contemporary English Version has “the lambs were killed for the Passover celebration.” Another possible model is “he had them kill the male lambs and kids for the celebration.” When studying the models of the various English translations, such as Good News Bible and Contemporary English Version, translators should keep in mind that they should be used only as guides to decide the best way to translate the text. They should never copy any of these models unless they represent what is the best style in their own languages.
On the fourteenth day of the first month was the normal time for the Passover (see Exo 12.6; Lev 23.5). The first month refers to the first month of the Hebrew calendar year, which corresponds to mid-March to mid-April in the modern Gregorian calendar and not to January. In the Pentateuch the first month is called Abib, but in the books written after the exile the first month is called Nisan. The fourteenth day would be approximately the end of March.
Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 1-2 Esdras. (UBS Helps for Translators). Miami: UBS, 2019. For this and other handbooks for translators see here.