21 But now the righteousness of God apart from the law is revealed, being witnessed by the Law and the Prophets, 22 even the righteousness of God, through faith in Jesus Christ, to all and on all who believe. For there is no difference; 23 for all have sinned and fall short of the glory of God, 24 being justified freely by His grace through the redemption that is in Christ Jesus, 25 whom God set forth as a propitiation by His blood, through faith, to demonstrate His righteousness, because in His forbearance God had passed over the sins that were previously committed, 26 to demonstrate at the present time His righteousness, that He might be just and the justifier of the one who has faith in Jesus. Romans 3:21-26
The righteousness of God is revealed in Jesus Christ. John the baptist declared Jesus as the Lamb of God who came to take away the sins of the world. Jesus lived a life that was without sin. Even though He became fully man and faced every temptation that we will face, He never sinned. Because of this His life was the perfect sacrifice for all humanity.
Without the shedding of blood there is no forgiveness of sins. Within the blood of a person is found life and when a person no longer has blood in their body they die. Blood is vital to a person’s life because it is the vehicle by which many nutrients our body uses to survive and live is transported. It is the precious blood of Jesus that washes away our sins and all who place their faith and trust in Jesus Christ are declared righteous before God.
Under the old covenant the nation of Israel was required to follow the law and every time the law was broken they had to be obedient to follow the appropriate sacrifice. It is impossible to keep the law of God and under the new covenant anyone who would simply place their faith in Jesus Christ is declared righteous.