When we talk about the old covenant Passover, we make a distinction between the Passover as first celebrated and the codified, permanent way it was later commemorated. That is to say, while some traditions established in the first Passover meal continued on, not every element given in Exodus 12:1–32 was performed year after year. For example, the Israelites did not spread blood on their doorposts once they dwelt in the Promised Land. Instead, they looked to the instructions given in passages such as Leviticus 23:4–8, Numbers 9:1–14, and Deuteronomy 16:1–8 to show them how to keep the feast once they settled in Canaan.
Numbers 9:1–14 establishes the importance of Passover in the life of the people of God. There was to be no Israelite who failed to keep the feast each year, for even the unclean or those travelling on a long journey were required to observe Passover, although their particular circumstances meant that they were allowed to do so the following month. The important part of all this is, of course, the requirement that no covenant member could get away with neglecting the feast that commemorated Israel’s redemption from Egypt. Anyone who did not keep the Passover would be cut off from the people (v. 13) — they would be excluded from the nation. They were risking their lives, as those who were cut off faced the possibility that the Lord might strike them dead (Gen. 9:11). There is probably a hint of eternal judgment in this phrase as well. Paul is probably alluding to this warning of being cut off when he cautions today’s believers against unworthily partaking of the Lord’s Supper, which is a new covenant expression of Passover (1 Cor. 11:27–32). Professing new covenant believers who fail to partake of the body and blood of Christ Jesus in faith risk God’s discipline. Moreover, the command not to miss the Passover in Numbers 9:13 likely should be taken as a caution for us today not to miss the sacrament when it is offered.
Once Israel was established in the Holy Land, Passover was celebrated each year in Jerusalem, the whole nation making pilgrimage there to keep the feast and recall God’s salvation (Deut. 16:1–2). Later generations of Israel would sing the hallel (Pss. 113–18) on their way to Jerusalem for the seder, or Passover meal. The final Passover Lamb Himself sang these psalms just before His own sacrifice (Matt. 26:30).