Leviticus 23:36

Ye shall offer — A several — offering each day. The eighth day — Which though it was not one of the days of this feast strictly taken. Yet in a larger sense it belonged to this feast, and is called the great day of the feast, John 7:37. And so indeed it was, as for other reasons, so because, by their removal from the tabernacles into fixed habitations, it represented that happy time wherein their 40 years tedious march in the wilderness was ended with their settlement in the land of Canaan, which it was most fit they should acknowledge with such a solemn day of thanksgiving as this was.