Also day by day, from the first day unto the last day, he read in the book of the law of God. And they kept the feast seven days; and on the eighth day was a solemn assembly, according unto the manner. Also day by day ... he read in the book of the law of God. This was more than was enjoined (Deuteronomy 31:10-12), and arose from the exuberant zeal of the time.
On the eighth day was a solemn assembly. This was the last and great day of the feast (Num. 30:35). In later times other ceremonies, which increased the rejoicing, were added (John 7:37).