Why aren't Christians Jewish? Since Jesus was a Jew, why don't Christians follow Judaism?

from the old testament

• From the beginning, God had a plan to establish a new covenant with all people. After Adam and Eve sinned, God told them and Satan the consequences of their sin. In one part, the protoevangelium, or “first Gospel,” God says to Satan, “I will put enmity between you and the woman, and between your offspring[e] and her offspring; he shall bruise your head, and you shall bruise his heel”(Genesis 3:15). In this, God pointed to Jesus, who would be victorious over Satan and his demonic forces. Jesus’ death on the cross made those who believe in Him righteous before God, removing the curse of sin. Believers follow Christ, not Judaism, because Christ is the ultimate fulfillment of God’s plan, His original covenant promise.
• In His covenant with Abraham, God promised that through Abraham “all the families of the earth shall be blessed” (Genesis 12:3; emphasis added). God’s covenant promise was a blessing for all nations, not just the Jewish people.
• God promised to make a new covenant with all people, not just Jewish people: “For this is the covenant that I will make with the house of Israel after those days, declares the Lord: I will put my law within them, and I will write it on their hearts. And I will be their God, and they shall be my people” (Jeremiah 31:33)

from the new testament

• During Jesus’ conversation with the Samaritan woman, He said, “Woman, believe me, the hour is coming when neither on this mountain nor in Jerusalem will you worship the Father. You worship what you do not know; we worship what we know, for salvation is from the Jews. But the hour is coming, and is now here, when the true worshipers will worship the Father in spirit and truth, for the Father is seeking such people to worship him. God is spirit, and those who worship him must worship in spirit and truth” (John 4:21-24). Jesus made it clear that though the line of the Savior came from the Jews, true worship was not about a place or a specific people group.
• In Acts 10, God shows Peter a vision of unclean animals (by Mosaic Law standards) and urges him to eat them. Peter resists initially, but he finally realizes that the vision is a metaphor showing that God’s love for all people; he says, “Truly I understand that God shows no partiality, but in every nation anyone who fears him and does what is right is acceptable to him” (vv. 34-35).
• Early apostles preached the Gospel of Jesus to Jews people and non-Jews alike. In fact, Paul confronted Peter about his hypocrisy in showing partiality to the Jews over Gentiles (Galatians 2:11-14). Paul wrote, “we know that a person is not justified by works of the law but through faith in Jesus Christ, so we also have believed in Christ Jesus, in order to be justified by faith in Christ and not by works of the law, because by works of the law no one will be justified” (Galatians 2:16). Believers are justified by Christ, not the law, so we follow Christ, not Judaism.
• Paul reminded new Christians that those attempting to return them to Judaism are not to be listened to and that the believers should stay the course of their Christian faith (Galatians 5:1-12). He writes in Galatians 5:6, “For in Christ Jesus neither circumcision nor uncircumcision counts for anything, but only faith working through love.”
• The book of Hebrews makes it clear that the new covenant under Jesus replaces the old covenant of Judaism (Hebrews 8:13).

implications for today

It’s hard to keep up with “the latest” in an age of technology. We’re comfortable with what is familiar even if it isn’t better.

Some of the Jews during the early church, such as the Galatians, felt the same, so they tried going back to the “old” ways of being justified by the Law rather than Christ. But Paul made it clear that “no one is justified before God by the law” and that “Christ redeemed us from the curse of the law by becoming a curse for us” (Galatians 3:11, 13). Jesus likened adherence to the Law to putting new wine in old wineskins and a new patch on an old garment. Maybe we could liken it to trying to use a floppy disc in a modern laptop. It won’t work.

Jesus brought the new and better covenant (Hebrews 8:6). The Old Testament is a part of God’s Word still, but laws about ceremonial cleanliness and animal sacrifices for sin no longer apply to Christians because Jesus became our final sacrifice for sin and changed the way we live. Jesus’ directions to His followers center more on the condition of our hearts toward Him and less on the strict rules from the old covenant.

So believers today live in freedom because of Christ. The Holy Spirit sanctifies us so that our hearts align with God’s will. This should compel believers to share that life-saving freedom with others who are enslaved to sin.