These are Rick Warren's exact words from his recent interview with Charlie Rose. Let me begin by saying that I have no desire to attack Rick Warren as a person. I truly appreciate the attention he is bringing to the AIDS crisis in Africa, though I profoundly disagree with some of the means he is employing in that effort.
That being said, to pretend as if the differences between Catholics and Protestants are minor reveals one of two things. He is either historically and theologically ignorant or he is willing to compromise for the sake of efficiency and expediency. I will give him the benefit of the doubt and assume that the latter is the case, especially since he indicates that "purpose" is what should bring us together. Catholics do not believe that we are saved by faith alone through grace alone on the basis of Christ's work alone. This is not "minor." Heaven and Hell hang in the balance.
Furthermore, to call for a reformation absent theology also reveals an unfortunate misunderstanding of what theology is. Theology is not just academic study consisting of musings over the nature of God. Theology is the basis for everything we do as Christians, including reaching out to alleviate the AIDS crisis. That sort of love is based on the loving character of Christ and the common grace of the Father, which are both part of theology (Christology and Theology proper). Additionally, the questions Warren is asking concerning the responsibility of the church is included in the study of theology as well. It even has its own name, Ecclesiology.
Doctrine will always matter in every area of our faith, including our practice.
I pray that the Lord will grant Warren repentance for his indifference to the Word of God and the theology that it teaches on every page.
"All Scripture is inspired by God and profitable for teaching, for reproof, for correction, for training in righteousness; so that the man of God may be adequate, equipped for every good work." - 2 Timothy 3:16-17