I could wish that no definitions had ever been felt to be necessary; and, still more, that none had been allowed to make divisions between churches.~ C.S. Lewis, Letters to Malcolm: Chiefly on Prayer
First, I want to clear something up. It has too long been an issue among Christians about which denomination you follow. Too many people think they go to “the best” denomination church, and sorry to be blunt, but I am sick and tired of it. Whether you attend a church that is Presbyterian, Lutheran, Baptist, Nazarene, Catholic, or any other, you’re not anymore of a Christian than the next guy that goes to a different denomination church.
What is important is what you think about who Jesus is and the things that he did. There is no one “right” or “better” denomination. We are THE CHURCH; we are all followers of Christ. Reality is, no matter which kind of church you attend, there are people who go every single Sunday that could be dying and going to hell.
There are people who go to Lutheran churches that aren’t actually saved.
There are people who go to Presbyterian churches that aren’t actually saved.
There are people who go to Nazarene churches that aren’t actually saved. There are people who go to Baptist churches that aren’t actually saved.
There are people who go to Catholic churches that aren’t actually saved.
Attending a specific denomination of church doesn’t save you, following Christ wholeheartedly and trusting in his sacrifice does. When these divides go up based on “denomination,” the Church as a whole is being weakened. From the outside looking in, this conflict within God’s people makes us look foolish to non-believers.
Parents and older believers, listen up! We must stop indirectly creating this mindset in the minds of young believers through how we speak about other churches. Making stereotypical jokes, speaking bad of another church, or simply vocalizing assumptions we have about a particular church based on their denomination further encourages this mindset among other believers. It must be stopped for the sake of uniting the church in the future.
The Bottom Line
Ultimately, the answer is no: Christianity cannot be invalidated simply because there are many different denominations. The truth is The Church is all of the people that love Christ and believe that they have received salvation by grace through faith and because of that, repent and turn from their sins. Furthermore, the Early Church differences in many denominations are what I would like to call “Nonessential pieces of Doctrine”, these are things that even though they are slightly doctrinally different, they are not a deterrent to the truth of the Church. Ultimately they have no bearing when it comes to trusting in salvation from Jesus by grace and through faith.