Romans 15:4

Can good Christians have bad theology?  Yes, they can; and many do.  Christianity is all about our relationships, first and most importantly, our relationship with God. It is possible for a Christian to have a good relationship with God, and still have some badly mistaken theological beliefs.  To put it another way, many Christians live better than their theology.  There is one particularly wrong belief that has a place in a small segment of modern Christianity.  That is a belief that the New Testament is a replacement for the Old Testament.  This belief holds that the coming of Christ and the writing of the New Testament made the Old Testament obsolete.  When pushed to its extremes this theology sometimes even seeks to disconnect the God revealed in the Old Testament from God revealed in Christ.

Paul would not have considered the possibility that this false belief is true.  When Paul spoke of scripture, the only scripture he knew was the Old Testament.  Paul wrote much of the New Testament.  He did not write it as a replacement of the old.  His writings illustrate how the revelation found in Jesus Christ was not separate from the revelation of the Old Testament, but was rather an extension and fulfillment of the Old Testament revelation.  Paul recognized that the God revealed in the Old Testament, is the same loving father, who sent his son Christ to die for our sins.

The scriptures are a testament to the mighty acts of God.  They revealed the many ways God has dealt with humanity from our creation to our salvation.  The testament of the works of God and godly people teach us the importance of endurance, and give us a basis for our hope.  In the scriptures, old and new alike, we find the teachings that give us encouragement when we need it most.  To discard the Old Testament is not only bad theology it is foolish.  All of God’s word is valuable for instruction.  Without the Old Testament, the Bible is incomplete.