A new convert asked, if the Pentecostal movement has only come into existence in the past two centuries, why should we call ourselves Pentecostal? Wouldn’t it be better to call ourselves simply Christians?
First of all, there has always been an Apostolic Church. Further, the NT Church was started on the day of Pentecost (this is why we use the term Pentecostal) and was led by the Apostles whom Christ chose (which is why we say we are Apostolic). You cannot be “of Christ” without following the Apostles doctrine.
There are a few great resources to show there’s always been a Church that stood for what the Apostles defined as necessary for anyone to be saved (repentance, baptism in Jesus name, and the infilling of the Spirit evidenced initially by speaking in tongues). From Jerusalem to Great Britain shows this well, even citing three Popes that endorsed Jesus name baptism. Marvin Arnold’s Apostolic History Timeline shows the same type of evidence. Thomas Weisser’s book After the Way Called Heresy is a short but good resource as well. History clearly shows multiple examples of this. For example, Martin Luther, in his work the Babylonian Captivity of the Church, discusses some baptizing in Jesus name. Or when we see multiple times where Catholic leadership is trying to “reign in” monks who dare to “baptize in the name of Jesus only” throughout the Middle Ages. This clearly shows the truth of God having an Apostolic witness throughout Church history. There is always a faithful remnant somewhere, even if it got down to just eight souls in Noah’s day.
It really is true that other man-made doctrines came later and are not original to the Bible (the trinity, being saved at repentance only, infant baptism, sprinkling as opposed to immersion, praying to Mary, communion as necessary for salvation, etc.). Many have rejected salvation which God gave us on the day of Pentecost (Acts 2) and “do church” in a way foreign to the way the Apostles did. This is why we define ourselves as Apostolic Pentecostals. It simply means we are biblical Christians. There are others who reject reading and implementing the Bible in a way that’s true to Jesus and the Apostles, and even their name gives this away (Baptists, Methodists, Catholics, Presbyterians, etc.).
The term Christian is so widely used today; even other groups define themselves by other terms. It helps identify what’s important to them, and this enables us to state beliefs clearly when we share our beliefs with friends. Even non-denominational means something as a term. There is a criterion to call yourself that. So these are short-cut ways to define ourselves theologically. They’re helpful to start meaningful conversations about what each person who uses the term Christian believes. If the term Christian wasn’t misused to represent views that remove people from what Jesus endorsed and the God-ordained Apostles taught, then the term Christian would be enough. It was in biblical times but that’s because they were Apostolic in doctrine and Pentecostal in experience.