Israel was given the Law, but it was not possible for people to follow it completely.
To save man, God sent his Son as a substitute for the massive blood sacrifice that would be needed to redeem us all. He did this becuse of His love for Mankind. It is a gift.
It is important to understand that our sinfulness and our separation from God was a rule as absolute as the law of gravity. God had set up the rules, and Satan enticed man to break them. God used Jesus to defeat Satan and reclaim Man for His own.
Amen!