There are many Christians around the world and they are also divided according to religion. It is very diverse that even if you say one is Christian and you think you have the same views as you also is a Christian. It is not the case as if you will talk with each other you can find the differences. Just like when there are two groups of religious men at the time of Jesus. The Sadducees and the Pharisees exist together but with differences in their doctrines.
You can now listen and watch the internet many videos of sermons or homily or presentations of many churches about their life of faith and share their experiences. they like to give testimonies on how meeting Jesus changed their life. They have made it their mission to share the truth and so they also preach. Some boldly preach even to higher people. You can watch many pastors of different churches with one denomination give their own sermon and interpretation of the Bible.
It is interesting to see or watch something that talks about sharing the gospel or truth they believe into. Even if the same Christians but they do not know each other and they do not make effort to be of one but they like to establish their own churches and create their own members. That is why there are many churches around the world with small or big differences. But they are united to say that they should also evangelize especially people in the communist country.