The Old Testament doesn’t contain our law or covenant for today (De 4:13; Ex 20:8-11). It’s purpose was to bring us to Christ, and now that Jesus Christ came, we’re no longer under the law (Ga 3:19, 24-25). It “died” when Jesus died, completely fulfilling the law and covenant (Co 2:14-17).
And yet, Christians still have the Old Testaments in their Bibles and even study the Old Testament. Why?
The Old Testament is Scripture. The Old Testament was revealed by God Himself. Paul wrote: “All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness” (2 Ti 3:16)
History. The Old Testament contains records of our physical (creation) and spiritual (God’s plan of redemption) heritage.
Sin and salvation. God knew man would sin and had a plan to redeem him (2 Ti 1:9-10). The Old Testament records sins and their consequences. We see God choosing and guiding a family (Israel) through which the Savior, Jesus Christ would come to redeem mankind.
God keeps His promises. Many promises are made by God and consistently kept in Scripture. He will not, and cannot lie (Ti 1:2; He 6:18). The Old Testament vividly shows that God will do what He says so we can trust that God will certainly both judge and reward as He has promised.
Important examples. Not only do we have examples of God’s character, but also many people we can imitate or learn from their mistakes (Jude 7; 1 Co 10:1-12; He 11; Ja 5:10).
References and quotations. The New Testament quotes or refers to the Old Testament over 300 times. We will understand the New better when we understand the Old better.
Types and anti-types (shadows and realities). Many people, places, and things in the Old were pointing toward the New (He 8:5; 10:1; Co 2:17). They can help us see and understand their fulfillments in the New.
Prophecy. There are many Old Testament prophecies that especially help us identify Jesus as the Christ.
Eternal principles: Although it is not our law, the Old Testament contains God’s original intentions for some things (compare Ge 1:27; 2:24 and Mt 19:8). Jesus many times said things like, “Have you not read…” – saying that they should have known and learned principles from the Old Law.
“For whatever things were written before were written for our learning, that we through the patience and comfort of the Scriptures might have hope” (Ro 15:4)