9:1 In the first month of the second year after the exodus, the Israelites celebrated their second Passover, just two days after the receiving of the tribal offerings (7:12-88), and two weeks before the first military census (1:2-44).
9:2-4 The Israelites were instructed to observe the Passover at its appointed time as outlined in Ex 12:12-40. The original Passover lasted only one evening as the Israelites departed from Egypt in haste, but later guidelines dictated that this celebration last for one week, beginning on 14 Abib (later called Nisan). Participants were required to be in a state of ceremonial purity in order to join in the celebration.
9:5-7 Biblical case law arose out of circumstances experienced by the community of faith. Questions of obedience to the commands of God were posed to the leading interpreter of the law, such as the high priest, another priest, or a Levite, who would then seek God’s will in the matter.
9:8-13 The legislation of vv. 10-13 probably served as the historical precedent for the second month Passover in the late eighth century BC, during the reign of King Hezekiah (2Ch 30:1-27), after the king had led the people to destroy pagan worship centers in and around Jerusalem. That celebration lasted the full week in accordance with the normal Passover, or unleavened bread sequence (Ex 12:14-20; 23:15), although Nm 9 does not contain stipulations for the week-long celebration of the Festival of Unleavened Bread in the second month. That legislation probably arose in the planning of the great celebration of King Hezekiah’s era.
9:14 Israelite law gave considerable attention to the status of resident aliens who identified with the Israelite religion. The same law applied to the native Israelite and to the alien. Note the cases in 15:14-16 and Ex 12:49. Second Chronicles 30:25 also notes that sojourners came to celebrate Passover in the days of King Hezekiah from all the former tribal territories of Israel as well as Judah. This would have included many people who had been deported by the Assyrians from Babylon, Cuthah, and other countries (2Kg 17:24). Anyone who wanted to identify with the Israelite community of faith and who was willing to submit to the Lord’s laws and statutes was permitted to do so.
At the word of the Lord they set out,
the descendants of Israel,
and at the word of the Lord
they camped; all the days that it dwelt,
the cloud upon the tabernacle,
This “Song of the Journey” set the stage for the actual departure from Mount Sinai in 10:11-36. The same sequence of marching and camping recurs in chap. 33. The NT also depicts God’s presence in the imagery of the cloud, as in the transfiguration of Jesus (Mk 9:7; Lk 9:34) and at his ascension (Ac 1:9).
9:19-22 The periodic movement of God’s presence from one campsite to the next varied from a day to several months—perhaps a year or more at Kadesh-barnea after the people refused to enter the promised land (13:25-14:38).