In Romans 3:21-26, we learn how Jesus purchased salvation for both Jew and gentile. In verses 21 and 22 of Romans, the Apostle Paul explains how the righteousness of God was revealed through Jesus Christ when he entered the world. After the fall of Adam, sin entered the world, and the relationship between God and man became hostile. Man needed a mediator to restore that relationship with the Father. So, the Father sent his son to save humanity from their sins. Paul how Christ accomplished this through his death in three analogies.
The first analogy was the metaphor of the slave market, which was for the Gentiles. Christ redeemed us from our sins, like how slaves were redeemed from the slave market. By his grace, we were set free. The second analogy was the metaphor of the law, which was for the Greeks. Christ justified us, which means that he declared us righteous, like how a judge declares someone innocent in a court of law. The third analogy was the metaphor of sacrifice for the Jews. Just like priests in Jewish tradition would make atonement for the sins of the people by shedding the blood of a lamb, God sent his son to die to make atonement for the sins of the world.
Christ became a substitute for us. We were the ones who should have died because of the sins we committed, but he paid it all through the shedding of his blood. God’s justice has to be satisfied. Christ’s atoning sacrifice reconciled mankind to God and made us just before him. Paul explains that we receive our justification by placing our faith in Christ to save us. This means that we freely receive God’s grace, which is his unmerited favor. It is something we can work to obtain. This is why we are saved by grace through faith alone.