I was reading the book of Romans and Romans 4:23-25 jumped out at me; it reads:
“Now not for his sake only was it written that it was credited to him, but for our sake also, to whom it will be credited, as those who believe in Him who raised Jesus our Lord from the dead, He who was delivered over because of our transgressions, and was raised because of our justification.”
In this passage, Paul is drawing a parallel between our faith and the faith of Abraham1. What particularly interests me in this passage is the phrase “for our sake also”. What a great gift that God would reveal and preserve His words for us! The Old Testament was written to help us. Clearly, Paul has a specific Old Testament verse in mind when he says that it was written “for our sake also” (that verse is Genesis 15:6), but the fundamental idea is that the sovereign and revelatory God has seen fit to reveal a bit of Himself and His plans to mankind. What a blessing this is! Knowing this truth ought to encourage you to appreciate and study the Old Testament (and the entire Bible). Of course, we need to be careful how we apply Old Testament passages, but let’s look at the Bible as a gracious gift even as we wrestle with difficult and challenging texts. They are written for our encouragement2.
You can find some more reasons to read the Old Testament here.