Note: Significantly updated on September 3, 2007
The Old Testament defines various laws, some of which are applicable to us, and some of which were applicable only for a time, for a specific place (Israel) and specific people (the Jews).
Before The Fall Adam and Eve didn't need written instructions because God's law was written in their heart. This law is summarised by Jesus in Matthew 22:37-39:
Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind.
This is the first and great commandment.
And the second is like unto it, Thou shalt love thy neighbour as thyself.
The same law is given in the negative, in its “Thou shalt not” form in Ex. 20:1-17. This is the same law because when something is affirmed, the opposite is denied. The form given in Ex. 20 is more suited to our nature after The Fall. Our hearts do no longer understand a statement like “Thou shalt love thy neighbour”. If I love my neighbours wife, our deceitful heart has a multitude of excuses: it's better for my wife if I separate because I don't love her anymore, so she can start afresh. Or my neighour is such a brute, his wife would be much better off with me. These are all carnal reasonings of our deceitful heart (Jer. 17:9). A statement like “Thou shalt not” is less likely to be misunderstood.
We see the same principle is at work in the constitution for New Zealand made by the New Zealand Libertarianz Party. It is mostly in the negative form, because as we have seen, even the United States of America has slowly turned into a European Socialist state, despite having a constitution so firmly opposed to these things. The current US nanny government would have appalled the framers. To make sure that such does never happen again, the Libertarianz have framed their constitution in the negative form:
The government shall extract no compulsory tax or involuntary contribution of any kind from any citizen for any purpose whatsoever.
But back to the various laws in the Old and New Testaments. It is almost undisputed that lying and stealing ought not to be done whether under the Old Testament dispensation or under the New Testament. It is also clear that the gentiles were not asked to keep every law that was given in the Old Testament. For example on the Apostle's Convent (Acts 15:6-31) (52 AD) the question was settled whether the gentiles needed to be circumcised and keep the law of Moses (Acts 15:5). The answer was no. Therefore, let us consier which parts of the Old Testament are eternal and which parts of it were for a specific people, a specific time and/or place.
To answer that question, we can divide the laws in the Old Testament into four categories:
And as with all other laws, we have to obey them, until the lawgiver revokes them. Jesus affirms this in the New Testament (Matthew 5:17-18), where he says:
Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.
For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.
The moral law is the part that was valid from the creation onward. It's the part known as the Ten Commandments. For example before The Fall God resteth on the seventh day. This part of the law is eternal, because love is eternal. Faith and hope will no longer be needed in heaven, but charity remaineth.
The second and the third categories of the law are called “the law of Moses” in Acts 15:5. Because the discussion wasn't if people should be allowed to steal. I.e. the law of Moses as mentioned there must of necessity mean something else than the Ten Commandments.
When God gave the land of Canaan to the seed of Jacob, he also gave them specific instructions on civil governance. This part is the civil law. It is only valid for a specific place, and although we can learn from it, it cannot be transplanted easily to other societies, nor does it have to be. For example when someone had committed accidental manslaughter, he had to flee to a city of refuge. There were six of them, see Num. 35:14, three on each side of the Jordan. That is of course a law that was applicable only for a specific place, i.e. Israel.
Before Jesus was born, the Jews also obeyed the ceremonial law. All the things in this law were as a finger pointing towards the coming of him that would fulfil the law. In theological language it is said that these laws were typical of Christ and his work. But after Jesus' sacrifice this part of the law was fulfilled, Matthew 5:18. God rented the veil of the Old Testament temple from top to bottom, Matthew 27:51, as a sign that the days of the ceremonial law were over. And as per Acts 15:28-29 we do not have to keep the law of Moses.
Then we come to the final category, the law given to the church of all times. This church is one church, whether under the Old Testament dispensation or the New Testament dispensation. For example Abraham and his seed were instructed to keep the covenant, Gen. 17:9. Clearly this was not a law given by Moses. All believers are the seed of Abraham, Rom. 4:16-17. He is the father not only of the Jews, but also of the New Testament Church. This church still has to keep this law, to keep the covenant. The rite has changed though. In the Old Testament circumcision and the shedding of blood was the manner in which this keeping of the covenant was performed. In the New Testament believers baptise their children. But both rites signify the same thing: the cleansing work of the Holy Ghost.
I believe I've now said enough on this subject. Let me address one last subject. Between Christians there is usually little division on how one should live, though the arguments do certainly differ. For example some do away with the Old Testament altogether, but introduce the law of the gospel, arriving at mostly the same conclusions to whether one is allowed to lie, steal, etc. There's one huge difference though, and that is if one should keep one day separate from the others, or as it is called keep the Sabbath. From the fact that God himself resteth on the seventh day it is already clear that this law wasn't invented by Moses, but present before The Fall. But in our days, many who call themselves Christians reject this. In practice this means that they take the day off, but expect the poor and the unskilled, who have less bargaining power in the market place, to work for them seven days a week and provide the well-off Christians with their amenities 24/7.
The New Testament clearly recognises a day of rest and of separation, although the lawgiver has changed the day. In the Old Testament the Saturday, the last day of the week was the day of rest, and sanctified by God's own example. In the New Testament this has been changed to the first day of the week, the Sunday (Acts 20:7, Rev. 1:10), and again sanctified by Christ's own example in appearing to his Church on that day.