Throughout the Old Testament, before Jesus was born, many prophets and messengers were sent by God to lead the people back to Him. But each time there were still some people living unrighteously and going against the commands of God. Even some of the people chosen by God had sinned against Him.
Fast forward to the crucifixion, we can see how deeply God loves us that He sent His only begotten son to die for us. Jesus came to complete the Law. Now we get to go straight to God through the Messiah – the perfect High Priest. Oh, how He loves us!