2 Chronicles 30:21

And the children of Israel that were present at Jerusalem kept the feast of unleavened bread seven days with great gladness: and the Levites and the priests praised the LORD day by day, singing with loud instruments unto the LORD.

The children of Israel ... kept the feast The time appointed by the law for the continuance of the feast was seven days; but in consequence of its having been allowed to fall so long into desuetude, they doubled the period of celebration, and kept it 14 days with unabated satisfaction and joy, materials for the additional sacrificial meals, amounting to 2,000 bullocks and 17,000 sheep, being supplied by the munificence of the king and the princes. There would be more even than those mentioned; because the general law at all the great festivals was, none should appear before the Lord empty (Exodus 23:15; Deuteronomy 16:16). [These private and voluntary offerings were called chªgiynaah, a festival.]