The Old Testament can be intimidating for many Christians. It talks about things that happened a really long time ago in a really far away place among really foreign cultures. There’s lots of blood and judgment and other stuff that sometimes offends our delicate, modern sensibilities. So, for many, the pages of our Old Testament tend to stay a bit crispy in our Bibles.
But, that shouldn’t be for many reasons, but I will offer you one really important really. Graeme Goldsworthy offers the most compelling reason for why we should study the Old Testament:
The most compelling reason for Christian to read and study the Old Testament lies in the New Testament.
The New Testament witnesses to the fact that Jesus of Nazareth I the One in whom and through whom all the promises of God find their fulfillment. These promises are only to be understood from the Old Testament; the fulfillment of the promises can be understood only in the context of the promises themselves.
The New Testament presupposes a knowledge of the Old Testament. Everything that is a concern to the New Testament writers is part of the one redemptive history to which the Old Testament witnesses.
The New Testament writers cannot separate the person and work of Christ, nor the life of the Christian community, from this sacred history, which has its beginnings in the Old Testament. (Taken from The Gospel and the Kingdom. Crownhill, MK: Paternoster Press, 1981. P. 18-19.)