In accordance with the directions of David king of Israel and the magnificence of Solomon his son: This first half of the verse refers to 2 Chr 8.14-15. The directives of David referred to in 2 Chronicles are more general, but here they apply specifically to this Passover occasion. The Levites had to carry out the Passover instructions given by David. The magnificence of Solomon his son may be rendered “the splendid way they were carried out by Solomon his son” (similarly Good News Bible) or “the magnificent way that Solomon his son carried them out.”

Stand in order in the temple according to the groupings of the fathers’ houses of you Levites, who minister before your brethren the people of Israel: The Levites had to position themselves in such a way as to be able to help every fellow Israelite. Your brethren are the people of Israel. This sentence may be expressed as “You Levites, who serve your fellow Israelites, must arrange yourselves in family groups and stand in the Temple” or “You Levites must organize yourselves in family groups and stand in the Temple, where you will serve your fellow Israelites.”

Here are alternative models for verses 4-5:

• 4 Josiah told them, “You are no longer required to carry the Covenant Box from place to place. Simply worship the Lord your God and minister to Israel, his people. Now, get all your families and groups of families ready to observe the Passover 5 according to the directions given by King David of Israel, and in the splendid way they were carried out by his son King Solomon. All you Levites, who serve your fellow Israelites, organize yourselves in family groups and stand in the Temple.

• 4 Josiah told them, “I do not require you any longer to carry God’s Covenant Box from place to place. What you must do is simply worship the heavenly ruler God and minister to his people, the Israelites. Now, get all your families and clans [or, family groups] ready to celebrate the Passover Festival [or, Fiesta], 5 following the directions [or, instructions] that King David of Israel has given to you. You must do them in the splendid way that his son King Solomon performed them. So, all you Levites, who serve your fellow Israelites, arrange yourselves in family groups and stand in the Temple.

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.