Why are there so MANY Denominations in Christianity?
This question is very complex, and spans the course of the past two thousand years, and especially the past five hundred. I am also not going to go into church history, but rather simply offer my opinion as to why there are so many denominations.
In a nutshell it's because people are different. Some are quite honest and are sincerely seeking to know God, and to follow Him no matter where it leads: whether it be to fight for freedom in Iraq or Afganistan, become a missionary in Peru, become involved with a church ministry, start your own ministry to the poor, help out at a local Homeless Shelter or Crisis Pregnancy Center, or to start your own church.
However, many people who name the name of Christ are simply seeking to become as wealthy as possible, or to marry the prettiest woman and try to make her happy, or to seek continual pleasures, etc... And some of these people also want to appease their conscience a bit, and so they look for the most comfortable church they can find... and that is where they attend. Others were born and baptized in a certain denominational church and that is all they know: so as long as the church is meeting their needs, that is where they stay. Many others simply attend church on Sundays, or whenever the urge tells them to go, and never get involved beyond perhaps giving some of their money to the church.
Others claim to know the Lord, but simply stay home, week after week, month after month, year after year. They do so because they say that: "The church is filled with hypocrites", or because they were hurt by someone in the church, or because their parents made them go when they were young and they didn't like it, or because they think that because God allows evil and pain and suffering (and even death) in the world, that He must either not exist, or (if He does) they want nothing to do with Him. However, of this you can be certain: if someone isn't seeking to Know and Serve God, they WILL HAVE AN EXCUSE as to why they aren't.
Also, I am almost certain that within many churches are those who are quite sincere, and who are sincerely seeking to know and to do God's will, and others who are simply playing church and playing games with God.
I once had a Christian friend who told me the following: He said that if you jump this high (with his hand about a foot off the ground), then the next thing you know God will ask you to jump this high: now lifting his hand another foot off the ground. And if you do that, then next thing you know He will ask you to do more, and jump higher, and higher, and higher. And as he spoke he lifted his hand each time. And then he said to me that he was not intending to keep jumping higher and higher for God, but that he would settle for where he felt comfortable, and that is where he would stay. He also left the church where we met soon afterward and went back to his old denominational church he grew up in, and as far as I know, that is where he stayed. And whether or not he is a Christian I cannot say; however, he said he was. The Point I am making though is that the Lord wants All of us, and that when we become Christians, NOTHING that He asks us to do is too much. That's because He gave His very Life for us: to the point of Dying a humiliating Death on a Cross. And His Death was NOT in vain either, for in it lies the very Power of God to save anyone who asks. I Cor. 1:18-2:5; Rom. 10:4,13.
However, the danger is that if all we want is to be Comfortable in our walk with the Lord, and are never willing to take Risks, or to become involved in ministry, or in things that S-T-R-E-T-C-H our faith, then we need to ask ourselves two important questions:
1. Are we indeed Saved? In other words, do we really KNOW the Lord? And
2. If so, are we willing to settle for less than God's best for our lives?
One way to be certain of your salvation is to ask yourself: Does God ever convict you of sin? And when He does, do you make any sort of changes to try and avoid it? Another way to be fairly certain you are a Christian is whether or not you shy away from other Christians, and from visiting other churches and church meetings, and Christian radio and TV programs. For the Scriptures tell us that Christians LOVE other Christians (Psalm 16:3) and that they also are (pretty much) in agreement with one another: at least on the major doctrinal issues (I John 4:6). Christians also don't shy away from hearing or reading the Scriptures (John 8:47). Also, does the Lord ever "speak" to you about anyone or anything? If not, then you need to ask yourself whether or not you are in the faith (Rom. 8:9). For more on this subject see:
Signs of a Christian
Why Does God Allow Evil?
Is Everyone a Child of God?
Comments on Various Denominations