Question: "What did the Law mean when it referred to a lasting ordinance?"
Answer: The phrase “lasting ordinance” is used 25 times in the NIV Old Testament, almost exclusively in the Books of Moses. The word translated “lasting” is the Hebrew olam, meaning “forever” or “for a long time.” In other words, a lasting ordinance referred to an ongoing command.
The first mention of a “lasting ordinance” is found in Exodus 12:14: “This is a day you are to commemorate; for the generations to come you shall celebrate it as a festival to the LORD—a lasting ordinance.” This command is in reference to the first Passover. That feast would become a yearly tradition practiced from that time forward. Instead of a one-time event, the Passover was to be a lasting ordinance.
In addition to the Passover, the ongoing burning of lamps in the tabernacle was to be a lasting ordinance, according to Exodus 27:21. The lamps in the tabernacle did not last forever, as the tabernacle would later be replaced by Solomon’s temple, and that was later destroyed. The idea behind a “lasting ordinance” was that the law would be ongoing rather than just for one occasion.
The Levitical priesthood of Aaron and his sons is also listed as a lasting ordinance (Exodus 29:9), as was the command for them to wash before entering the tent of meeting (Exodus 30:20–22). In Leviticus, lasting ordinances include not eating the fat or blood (Leviticus 3:17), priests abstaining from alcohol (Leviticus 10:9), the yearly Day of Atonement (Leviticus 16), sacrifices only brought to the priests at the tabernacle (Leviticus 17:1–7), the yearly Jewish festivals (Leviticus 23), and lamps, olive oil, and bread before the Lord in the tabernacle (Leviticus 24:1–9).
In Numbers, more lasting ordinances are mentioned: the blowing of trumpets when the community was to move (Numbers 10:1–10), offerings (Numbers 15:15), the call for Levites to oversee the work of the tabernacle (Numbers 18), and rules related to ritual cleansing (Numbers 19).
Outside of these books, only two passages mention a “lasting ordinance.” In 2 Chronicles 2:4 a lasting ordinance is made concerning moving the tabernacle worship to the Jewish temple in Jerusalem. Then, in Ezekiel 46:14 a lasting ordinance is given related to a future temple prophesied by the prophet Ezekiel (usually called the Millennial Temple).
As these passages note, the idea of a lasting ordinance indicated an ongoing law, but it was not always intended to be eternal. In addition, the lasting ordinances of the Bible are related to the tabernacle, temple, and worship practices of the Jewish people. The first and perhaps most well-known of these practices was the Passover, the lasting ordinance that marked the new beginning for the Jewish people. All of these lasting ordinances were commanded by God to the people of God as ways to obey and honor Him.