We read about the old covenant in the Old Testament of our Bible. The laws of human conduct given to Moses; the sacrifice of innocent animals for repentance of sin; and the need for priests to enter the presence of God to intercede for the people who would die in God’s presence on the mountain or the Holy presence of God in the tabernacle or temple. Then God sent his Son with the new covenant!
Jesus described to a Samaritan woman at Jacob’s well a new relationship with God he makes possible. God is Spirit and it no longer matters where or when you worship him, but only that you worship him in spirit and in truth. Jesus later told others that he is the way, the truth and the life and no one comes to the Father except through him. He shed his innocent blood on the cross as a once and for all sacrifice for sin, replacing animal sacrifices. When Jesus died, an earthquake tore the heavy curtain from top to bottom that separated God’s holy room in the temple from worshipers, demonstrating that we can now enter God’s presence without fear in the name of Jesus Christ.
There are some preachers who claim the laws of the Old Testament don’t apply to Christians because we are under grace and not law, but that is NOT what Jesus teaches us. Jesus makes it clear that he didn’t come to replace God’s laws of human behavior, but to add spiritual laws for us to follow as well. It is no longer enough not to kill someone, we must not hate them. It is no longer enough to refrain from the physical act of adultery, we must not lust after someone in our heart who is not our wife or husband. We are not saved by obedience to the law, but as followers of Jesus Christ, we must be obedient to our heavenly Father. The parental rules he has established for his sons and daughters have not and will never change.