Deuteronomy 5:33 Ye shall walk in all the ways which the LORD your God hath commanded you, that ye may live, and that it may be well with you, and that ye may prolong your days in the land which ye shall possess.
These laws would accomplish two purposes. The major thing is that they would show them their need of a substitute to die in their place when they failed. The second purpose would be that God would give them successful lives. They would live longer and better by doing the things that God told them to do.
The laws were given to show them a lifestyle that would be better than all the nations around them. He knew that they would fail so a sacrifice system was put in place. We need to know that God is always thinking of what is best for us!