My question is that is seems the great majority of Christians claim to follow the Bible as the Word of God. Why are there Catholics, Baptist, Lutherans, etc. etc.? Actual Christians do endeavor to follow the Bible as the Word of God. The reason there are denominations are manifold, and not all of them are so-called Protestant. There are denominations known as Rites within Catholicism, are there not? What is the difference? Different emphases, different ceremonies, different rites, focusing more heavily upon one aspect of Scripture than another denomination, which focuses more upon another. But, both are Scriptural, both are sound of doctrine, both are Christian.
There were seven churches in Paul's time, all had strengths and weaknesses. He both lauded and chastised each. It is no different now. Christians will agree upon fundamental salvific matters, that Jesus Christ was the Son of God, born of a virgin, who was crucified, died a physical death and rose victorious over death and sin on the third day for the salvation of all who repent and believe on Him. These are the "church," the Body of Christ, which knows no denomination.
He both lauded and chastised each. It is no different now.
I was walking across a bridge one day, and I saw a man standing on the edge, about to jump off. So I ran over and said, "Stop! Don't do it!"
"Why shouldn't I?" he said.
I said, "Well, there's so much to live for!"
He said, "Like what?"
I said, "Well...are you religious or atheist?"
He said, "Religious."
I said, "Me too! Are you Christian or Buddhist?"
He said, "Christian."
I said, "Me too! Are you Catholic or Protestant?"
He said, "Protestant."
I said, "Me too! Are you Episcopalian or Baptist?"
He said, "Baptist!"
I said,"Wow! Me too! Are you Baptist Church of GOD or Baptist Church of the Lord?"
He said, "Baptist Church of GOD!"
I said, "Me too! Are you Original Baptist Church of GOD, or are you Reformed Baptist Church of GOD?"
He said,"Reformed Baptist Church of GOD!"
I said, "Me too! Are you Reformed Baptist Church of GOD, reformation of 1879, or Reformed Baptist Church of GOD, reformation of 1915?"
He said, "Reformed Baptist Church of GOD, reformation of 1915!"
I said, "Die, heretic scum", and pushed him off.
-- Emo Phillips