Why, then, was the law given at all? It was added because of transgressions until the Seed to whom the promise referred had come. Galatians 3:19
An earnest young couple saw me reading my Bible and told me, "We just took a course on Romans. Our preacher told us that you've got to keep the law." Can you imagine a more contradictory statement?
Yet they were so proud. They had just acquired some false doctrine by listening to a preacher instead of reading the Word. I turned to Romans and showed them verses that proved just the opposite. If you could only cite one book of the entire Bible to prove that we are justified by faith alone, it would be Romans.
I dread the words "My preacher says", for unless he is describing his vacation, his words are final on nothing. In this case, it was as if a guide to the Grand Canyon were to say, "This is the tallest mountain in the world."
It is quite common to say that the Jews got the law as a giant step forward in the progress of humanity. Earlier, we supposedly learned of monotheism from Pharoah Akhenaten who worshipped the sun. As if Adam and Eve believed in more than one God. PROGRESS is ever the theme of the promoters of evolution.
I asked a group of Methodists ("Welcome, get yourself a cup of coffee!") if it was not wonderful how people keep getting better all the time. "Aren't people a lot better now than in the times of your parents and grandparents?" It was enough to make people drop their coffee.
We all expect progress to be cited as we move up from "lower life forms", but it is also promoted as an example of advances in theology. If the Devil ever takes a break, I haven't seen it.
So then, why was the law given? Abraham was justified long before the law was given, for he knew it was wrong to kill and steal, for examples. A nation arose that was so evil that they needed to be told so.
Steven's denounciation of Israel's evil practices, in Acts chapter seven, shows the condition of these people. It is as if the law turned to poison in their mouths, and the New Testament was given as the antidote.