It would take many pages to bring out all the differences between the Old Testament and the New Testament. The Old Testament is primarily a historical account of God’s dealings with the nation of Israel and the “covenant” (which is another word for “testament”) He made with them on Mount Sinai. That “covenant” is the Ten Commandments, along with other laws that instructed them in every area of their life. In Leviticus 18:5 God said to Israel, “So you shall keep My statutes and My judgments, by which A MAN MAY LIVE IF HE DOES THEM; I am the LORD” (NASB). In other words, God gave Israel a perfect standard to live by and He promised them LIFE if they could keep His laws. The problem was NO ONE COULD DO THEM! So why did God establish the Covenant of Law with Israel?  Romans 3:19-20 gives us the answer: “Now we know that whatever the law says, it says to those who are under the law, that every mouth may be stopped, and all the world become guilty before God. Therefore by the deeds of the law no flesh will be justified in His sight, for by the law is the knowledge of sin.” The Covenant of Law was a test for mankind (with Israel being a sample of the human race) and they “failed the test.” For 1500 years Israel proved that they could not live up to God’s standard of righteousness and thus the Law proved they were sinners in need of a Savior. The “covenant” had accomplished its purpose and this paved the way for another covenant to be established by God; the “Old Testament (Covenant)” would be replaced by the “New Testament (Covenant)”.

What is the New Covenant? Let’s read Luke 22:20: “Likewise He [Jesus Christ] also took the cup after supper, saying, ‘This cup is the NEW COVENANT in My blood, which is shed for you.” In this passage Jesus is instituting the Lord’s Supper and He is teaching His disciples that the cup of wine symbolized the blood He would shed on the cross so they could be forgiven. In the “Old Covenant” (of LAW) God was demanding holiness from men and then condemning them for failing; in the “New Covenant” (of GRACE) God was giving His Son as a sacrifice for sin so that men could have forgiveness of sins and eternal life. In the Old Testament, God had given many “pictures” and “prophecies” of Jesus Christ giving up His life and shedding His blood to provide salvation for lost and guilty man. In the New Testament we have the fulfillment of those pictures and prophecies. The gospels record Christ’s birth, His life, His death, His resurrection, and His glorious ascension to God’s right Hand (which is the foundation for the New Covenant). The rest of the New Testament gives us a history of the gospel of Jesus Christ going out to the entire world and the spiritual blessings that are given to everyone who believes in Christ as Savior.

Before I close this short and “limited” answer, I would encourage you to read 2nd Corinthians chapter 3 where the apostle Paul contrasts the Old Covenant with the New Covenant. He refers to the Old Covenant as a “ministry of death” (verse 7) and a “ministry of condemnation” (verse 9). In contrast, the New Covenant is called a “ministry of righteousness” (verse 9) because what the Law could not do (it could not give men a righteous standing before God), the gospel of Jesus Christ has done. It is no wonder then that Paul goes on to say, “For if what is passing away (the Old Covenant) was glorious, what remains (the New Covenant) is much more glorious” (verse 11).

I would also encourage you to study Hebrews chapters 8:1-10:22, where the inspired writer goes into great detail bringing out the need for and the superiority of the New Covenant over the Old Covenant. You will see that it is indeed a “better covenant” (8:6). You will also learn that believers today (who make up the church) are under all the spiritual blessings of the New Covenant and that in a coming day God will establish this covenant with the nation of Israel (see 8:8-12 & 10:16-17).  (226.7)  (DO)