Ceremonial laws were preparatory or typological. They dealt with how a believer maintains ceremonial cleanliness. This notion pointed beyond itself but there are a number of dietary, clothing, grooming, and physical statutes that an Old Covenant Jew had to honor.
They were temporary until the fulfillment of the New Covenant when the substance, Christ, came to usher in a Kingdom where the wall of division (in large part made by the ceremonial laws) was torn down. Even the entire Temple or Sanctuary was typological as Moses was shown a copy of the heavenly sanctuary to which we now have access through Christ.
Moral law is naturally, perpetually, and unchangeably binding. Positive law is given for a specific time, place, and circumstance. The ceremonial laws were positive in this sense. Regulations concerning government and worship are of this nature under the New Testament. They are not "ceremonial law" because that has been fulfilled by Christ in the tabernacle made without hands. They are not "moral law" in the sense of being unchanging and perpetually binding because they are given for the New Testament church on earth.
Nevertheless they are binding as laws because Christ as head has constituted the government and worship of His church. It might also be noted that the moral law itself teaches the binding authority of things which are positively appointed; the second commandment specifically binds men to observe any and every divine institution.
There are three uses for the Moral law (the Ten Commandments, first table being duty to God, second table being duty to our fellow man:
(1)
Civic Use – Goad to civil righteousness – the ten commandments serve the purpose of God’s common grace in the world at large to restrain sin and promote righteousness. Thus, for believers and unbelievers alike (as human beings created in God’s image yet fallen into sin), the moral law may function simply as a behavioral hedge (e.g., Romans 2:14-15).
(2)
Pedagogical Use – Tutor to drive us to Christ – the ten commandments also function as a tutor that leads us to see our need for Christ. In this way, we see how the law condemns us as law-breakers and shows us our need for the one perfect law-keeper, Jesus Christ (e.g., Romans 8:3-4; Galatians 3:23-24).
(3)
Teaching Use – Rule of life – for believers, and only for believers, the ten commandments also provide a guide for righteousness and holy living (e.g., 1 Corinthians 7:19; Romans 7:12, 22, 25). Thus, believers will learn to delight in God’s Law (Psalm 1:2; 40:8)
In the Covenant of Works, the command was "
Do this and live" or "
Do this in order to live."
With the Covenant of Grace instituted in the Garden after the fall of Adam, the command became "
Because you live, do this" or simply, "
Live, and do this." It is no longer "do this
for life", but rather "do this
from life." This is because Jesus fulfilled the Law for us and took upon Himself it's curse.
Our Lord did not prescribe any new law. There are no works of supererogation. He gives us the moral law out of His mediatorial hand as the perfect rule of righteousness, and explains the law in its original meaning according to its spiritual and perfect nature. Christ was made under the law and fulfilled all righteousness; His righteousness is perfect, and this righteousness is
imputed to believers for their justification.
If our Lord had given new precepts He would have needed to come again a second time to atone for our sins because we would have sinned anew in breaking those precepts and it would have required another work of obedience and suffering to save us. But as it is, thanks be unto God, He has appeared once in the end of the world to put away sin by the sacrifice of Himself. There is no new law, no new sin, no new sacrifice to be made for sin.
To dig deeper see:
https://www.monergism.com/marrow-modern-divinity-modernized-and-annotated-ebook
AMR