1 Kings 8:66 - Matthew Poole's English Annotations on the Holy Bible

Solomon having joined with the people in the solemn assembly, which was kept on the eighth day, in the close of that day and service he took his solemn farewell, and dismissed them with his blessing; and the next morning when the heads and elders who came to Solomon upon this special summons, above, 1 Kings 8:3, and with them divers of the people came to take their leave of the king, he sent them away. And so this place agrees very well with 2 Chronicles 7:9,10. They blessed the king, i.e. they prayed to God to bless him, according to their duty and custom. Or, they praised him, for his great care and pains in building of the temple, and setting up God's worship among them. The goodness that the Lord had done for David, in giving him a sure house, and a wise and religious son, by whom he had now fulfilled the promise made to David about the building of the temple.