New Defender's Study Bible Notes
9:1 the first month. Compare Numbers 1:1. The Passover was evidently observed before the order was given to take the census.
9:5 the fourteenth day. This was one year to the day after the first Passover supper and the beginning of their exodus. God had commanded that they observe this event on every future anniversary of it (Exodus 12:24-27).
9:12 nor break any bone. See also Exodus 12:46, Psalm 34:20. The Passover lamb was to be without blemish, which meant also that, although he was to be slain, none of his bones could be broken. The lamb was intended, of course, to be a type of the coming Lamb of God, whose bones were providentially kept from being broken on the cross (John 19:33-36).
9:16 So it was alway. This was another daily miracle during the wilderness years, in addition to the manna and the water. The shekinah cloud, assuring the people of God’s continual presence (Exodus 33:14), guided them by day and night, from the time they built the tabernacle (Exodus 40:36,38).