Israel found itself free from slavery in Egypt. God knew that they needed His law to order their society.
The Law reflects God’s character and shows us how far we fall below His standards. In the face of God’s Law, we should feel our need for God’s grace and mercy, and expect to grow in obedience.
Jesus fulfilled the Law. It is clear who is His by how they behave. It is not the behaviour which makes us Jesus’, but it does show whose we are.