2 Chronicles 29:21 Commentary - English Annotations on the Holy Bible by Matthew Poole
The number of seven is famous and customary in sacred matters, and is here used in regard of the vast numbers and various kinds of sins, the guilt whereof yet lay upon the kingdom, which was now to be expiated. Indeed, in case of one particular sin of ignorance done by the people, there was but one bullock to be offered, Lev 4:13,14, but here the sins were many and presumptuous, &c.
A sin-offering for the kingdom; to make atonement for the sins of the king, and the royal family, and the court.
For the sanctuary; for all the idolatry and uncleanness wherewith the temple had been polluted, which, as it had been cleansed naturally by the priests’ hands, so now was to be purged morally by sacrifices.
For Judah; for the sins of all the people of Judah.
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English Annotations on the Holy Bible by Matthew Poole
Matthew Poole (1624–1679) wrote English Annotations on the Holy Bible, completing the chapters as far as Isaiah 58 before his death in 1679. The rest of the Annotations were completed by friends and colleagues among his Nonconformist brethren. The first printing of the completed edition was in 1685, 2 volumes folio, followed by editions in 1688, 1696 (with valuable chapter outlines added by the editors, Samuel Clark and Edward Veale), and the 4th and definitive edition in 1700, the basis of all others.