As a Christian, you are under the new covenant or new testament which has been ratified with the blood of Jesus. It is natural that you should read and study the writings of the apostles and the teachings of Jesus because they apply directly to you. But don’t neglect the Old Testament scriptures. In referring to these scriptures, the Apostle Paul wrote in Romans 15:4 “For whatever things were written before were written for our learning, that we through the patience and comfort of the Scriptures might have hope.”
There are many things that you can learn from the Old Testament. I will mention a few things. The Old Testament tells you about God, how He created the world and how He destroyed the world with a flood because of man’s wickedness. It tells you how He dealt with the Israelites, His people; when they followed Him, He blessed them, and when they turned away from Him, He withdrew His blessings and destroyed many of them. He demonstrated His mercy and forgiveness when they repented. It describes His righteousness and His expectations for His people. It tells you how He dealt with the idolatrous nations and brought His wrath and destruction on many. The Old Testament is filled with prophesies that were given by God. When you see the fulfillment of prophesies, sometimes spoken hundreds of years before their fulfillment, it should build faith that He is the true God, for only God really knows what will happen in the future. The Old Testament gives you insight into the plan that God had for mankind; a plan developed before the creation. As much as anything, the Old Testament teaches you about God.
You also can learn much from the individuals described in the Old Testament. From Noah you can learn how God can save the righteous while destroying the wicked (Genesis 6 – 8). From Abraham you can learn how God counted him righteous because of his great faith and trust in God (Genesis 15). From Abraham and Lot you can learn that you should be hospitable because you might unknowingly be entertaining angels (Genesis 18, 19; Hebrews 13:2). From Lot you can learn that opportunities that look so good can be moving you toward wickedness (Genesis 13, 19). From Abraham you can learn that God may test you to prove your faith (Genesis 22). From Joseph you can learn that what men intend for evil, God can turn for good (Genesis 37 – 47). From Joseph you can also learn how God blesses those who maintain integrity and shun sin.
From Moses you can learn that even if you doubt your ability, God can use you to accomplish His will (Exodus 3 – 4). When the Israelites put the blood on their doorway in Egypt and saved their families, you can understand how the blood of Jesus can also save you (Exodus 12). From Gideon you can learn how God can accomplish much with little (Judges 6 – 8). From David you can learn how, with God’s help, you can slay giants (1 Samuel 17). From David you can learn how God blesses those whose hearts are set on pleasing Him (2 Samuel 7). From David you can learn how God can forgive even big sins (2 Samuel 12). From Solomon, you can learn how an ungodly spouse can turn you away from God (1 Kings 11). From Elijah you can learn that God answers prayer (1 Kings 17; James 5:17-18). From Elijah you can learn that when it seems that you are the only one who is faithful to God, he has reserved many others who are faithful to Him (1 Kings 18-19). From Job you can learn the need for patient endurance (Job; James 5:10-11). From Daniel you can learn that God can shut the mouths of lions that come against you (Daniel 6).
You can learn much from the description of the Israelites when they were in the wilderness. 1 Corinthians 10:5-11 “But with most of them God was not well pleased, for their bodies were scattered in the wilderness. Now these things became our examples, to the intent that we should not lust after evil things as they also lusted. And do not become idolaters as were some of them. As it is written, ‘The people sat down to eat and drink, and rose up to play.’ Nor let us commit sexual immorality, as some of them did, and in one day twenty-three thousand fell; nor let us tempt Christ, as some of them also tempted, and were destroyed by serpents; nor complain, as some of them also complained, and were destroyed by the destroyer. Now all these things happened to them as examples, and they were written for our admonition, upon whom the ends of the ages have come.”
My encouragement to you is that you read and study the Old Testament because there is much that you can learn from it.