Is there a difference between the Old and the New Testament?

These verses are from the Old Testament and the New Testament, and they teach the same thing. Some people say that the Old and the New Testament are different and seem to contradict each other at some points. Especially when Jesus says in Matthew 5:38, 39: “You have heard that it was said, ‘An eye for an eye and a tooth for a tooth.’ But I tell you not to resist an evil person. But whoever slaps you on your right cheek, turn the other to him also.”

These and other points seem different, but the reason why Jesus said that was because of what He was going to accomplish on the cross and offer forgiveness to humanity. This is the reason we need to do the same. If we are forgiven, we need also to forgive. The other point in which we see that there is a difference is the one about the sacrifices that Jewish people used to make for the forgiveness of their sins. The New Testament says that they are not needed anymore. Why? Because Jesus was that perfect sacrifice offered for us and can offer perfect forgiveness to those who believe in Him (Hebrews 10:11-14). What was done in the Old Testament times was just a shadow of what was about to happen in the New Testament (Colossians 2:16, 17, Hebrews 10:1).

The other example is the one with the circumcision. It was commanded in the Old Testament, but still, the New Testament says that doing it or not does not matter anymore, and it doesn’t please God (Galatians 4:6). Why? Because in the Old Testament, God was already looking for a circumcision in the heart (Jeremiah 4:4), and this is the point. What is commanded in the New Testament and the way Jesus said that things need to be done is not something new. It was already in the heart of God in the Old Testament. This is what He really meant by circumcision. The same is true with the sacrifices. He says already in the Old Testament that He doesn't need them (Hosea 6:6). He wanted people to understand the real meaning of those practices, not just to perform them blindly as traditions and rituals that needed to be followed.

We can say the same for consuming the meat of certain impure animals and so on. What really defiles us is what comes out of our hearts. This is where Jesus wants to work and establish a relationship with us. Our heart needs to be His home. Only He can cleanse it in a proper way. This happens when we invite Him to come in. What happened before is just a shadow of what is now in the New Testament times. It is just an example of what really needs to be done. Jesus came to accomplish the law. Not to abolish it (Matthew 5:17). With Him and the strength He can give us, we can really follow Him. He came to work and focus on what is inside us – our hearts. He wants to write His law there so we can follow Him with heart and not because we are forced to do it.