Different denominations all have differences in doctrine, in the way they perceive and interpret different pieces of scripture. Human nature takes over and, instead of learning to overlook differences and get along, they split off and form their own distinct group so they can snub and ignore others with slightly different ideas.
It's mainly different interpretations. Everybody knows the Westboro Baptist Church has an entirely different interpretation than what most Christians believe. And Catholics, well, I think they're more of an earthly church, which still confuses me. I believe it's episcopal that believe that if a person believes in god (or is of god) then he can change what the Bible says because he has authority. All in all, there are lots of interpretations.
I think God comes to us in a way we can understand. So different cultures will have different ways or names for God. I believe Buddha, Allah and God are all one and the same. As far as the Christian religions go I think different people learn in different ways. Some people want and need the fire and brimstone sort of teaching and some need a more laid back interpretation. But I feel if we all get to God, what difference does it make how?
The reason there are different denominations within Christianity is because the Bible allows for us to have differences of opinions. Within Christianity there are very few essential doctrines that define what it means to be a Christian.As long as a church believes in these essential doctrines, then it is Christian. However, there are many things in the scriptures that have been interpreted in different ways. For example, on what day of the week should we worship, Saturday or Sunday? Should we baptize by sprinkling or baptize by immersion? Do we take communion every Sunday, once a month, or once a year? The answers to these questions do not affect whether or not someone is a Christian. It is in these issues, and others like them, that denominations are formed. It does not mean that one denomination contradicts another. It means that though they agree in the essentials, they differ in some nonessentials. This is permitted in Scripture: (cont in comments)
The reason there are so many different denominations in Christendom is because many people do not accept the Bible as the final authority on various subjects and teachings.Instead of accepting what the Bible really teaches many tend to try and tweak what the Scriptures say in an effort to doggedly hold on to a teaching that the Bible really does not support. For example, the Trinity teaching, which states that there are three persons in one, but that there is only one God. No where in the Bible is this teaching supported. But many who refuse to accept what the Bible teaches seek to misuse various Bible texts in an effort to prove their case. An example of this is where those who believe in the Trinity try to use John 1:1 to prove that the Trinity is true. But in that same chapter at verse 18, the Bible clearly states that no one has ever seen God. Here is the point, if Jesus was God in the flesh then verse 18 would not be true because many saw Jesus. Clearly the Bible shows that Jesus was not God but who he says he was, the Son of God.
It's because, man has made it more about man. Yes most do preach from the Bible, but most of those have manuals, creeds, and confessions of faith that they also adhere to. I'm sure there are people here that say "ask Jesus into your heart / life and you'll be saved. Fact is that not one single time will you find that in the Bible. Not one single time will you find that the Bible teaches faith alone salvation. These churches get it from their manuals.
Many factors have contributed to the development of new religious groups. A comparison of their teachings and practices with the Bible indicates, rather, that the diversity of religions is because people have become followers of men instead of listening to God. Who is the instigator of such religious confusion? The Bible identifies Satan the Devil as " the god of this evil world, has made him blind, unable to see the glorious light of the gospel that is shinning upon him, or to understand the amazing message we preach about the glory of Christ." ( 2 Corinthians 4:4). It warns us " But I say, that the things which the Gentiles sacrifice, that sacrifice to devils, and not to God: and I would not that ye should have fellowship with the devils." (1 Corinthians 10:20). KJ Version Another version " No; but I say that the things which the nations sacrifice they sacrifice to demons, and not to God; and I do not want you to become sharers with the Demons." (NWT) How vitally important, then to make sure that we really are worshipping the true God, the Creator of heaven and earth, and that our worship is pleasing to him. And the only way you can do that is study the Bible, and decide who is really following Jesus and his teaching. People give their option rather then what the Bible teaches, and try to get followers after them selves.