The requirements, prohibitions, sacrifices of the Old Testament Law were not addressed to the whole world, but only to the unique nation of Israel. God made a covenant with them and required them to obey him. On the other hand, the teachings of the New Testament are directed both to Jews and gentiles: “…I had been entrusted with the task of preaching the gospel to the uncircumcised (gentiles), just as Peter had been to the circumcised (Jews),” Galatians 2:7. The New Testament and the teachings of our Lord Jesus, though rooted in the Old Testament, bring a new hope. Jesus offered the possibility of entering into a covenant with God personally. The Christian has a different covenant than the Law Covenant made with Israel in Old Testament. Hence, there are differences: such as the observance of the Sabbath, circumcision, meat consumption, the rule of “an eye for eye,” etc.
“The law is only a shadow of the good things that are coming…”Hebrews 10:1(NIV). “Therefore the law was our tutor to bring us to Christ…” Galatians 3:24 (NKJV).
The teachings of the Old Testament are the letter of the law and foreshadow the reality or fulfillment in the daily life of our Lord Jesus. “Which are a shadow of things to come; but the body is of Christ.” Colossians 2:17. Jesus fulfilled both the letter and the spirit of the law. Jesus explained that the Law focused on a person’s behavior but the spirit of the Law focuses on a person’s heart in Matthew 5:27,28 (NIV): “You have heard that it was said, ‘You shall not commit adultery.’ But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart.”
Another example of the letter foreshadowing the spirit is in Matthew 5:38-40(NIV), “You have heard that it was said, ‘Eye for eye, and tooth for tooth.’ But I tell you, do not resist an evil person. If anyone slaps you on the right cheek, turn to them the other cheek also. And if anyone wants to sue you and take your shirt, hand over your coat as well.” Remember: “…love is the fulfilling of the law.” (Romans 13:10)
The Bible is harmonious in its entirety. God is the author of both testaments. “All scripture is given by inspiration of God.” 2 Timothy 3:16.