Complete Commentary on the Whole Bible, by Matthew Henry, at sacred-texts.com
1 Chronicles 9:1
This chapter expresses that one end of recording all these genealogies was, to direct the Jews, when they returned out of captivity, with whom to unite, and where to reside. Here is an account of the good state into which the affairs of religion were put, on the return from Babylon. Every one knew his charge. Work is likely to be done well when every one knows the duty of his place, and makes a business of it. God is the God of order. Thus was the temple a figure of the heavenly one, where they rest not day nor night from praising God, Rev 4:8. Blessed be His name, believers there shall, not in turn, but all together, without interruption, praise him night and day: may the Lord make each of us fit for the inheritance of the saints in light.