"What is Trinitarianism? Is Trinitarianism biblical?"
 Answer:  Trinitarianism is the teaching that God is triune, that He has revealed  Himself to be three co-equal and co-eternal Persons. For a detailed  biblical presentation of the Trinity, please see our article on what the Bible teaches about the Trinity. The purpose of this article is to discuss the importance of Trinitarianism in regard to salvation and the Christian life.
We are often asked the question, “Do I have to believe in the Trinity to  be saved?” The answer is yes and no. Does a person have to fully  understand and agree with every aspect of Trinitarianism to be saved?  No. Are there some aspects of Trinitarianism that play key roles in  salvation? Yes. For example, the deity of Christ  is crucially important to the doctrine of salvation. If Jesus is not  perfect, His death could not have paid the penalty of sin. If Jesus is  not holy, He could not be the Savior, the Lamb of God who takes away the  sin of the world (John 1:29).  An unbiblical view of Jesus’ divine nature results in an errant view of  salvation. Every “Christian” cult that denies the true deity of Christ  also teaches that we must add our own works to Christ’s death in order  to be saved. The true and full deity of Christ, an aspect of  Trinitarianism, refutes this concept.
At the same time, we recognize that there are some genuine believers in  Christ who do not hold to full Trinitarianism. While we reject modalism,  we do not deny that a person can be saved while holding that God is not  three Persons, but rather simply revealed Himself in three “modes.” The  Trinity is a mystery, which no finite human being can fully, or  perfectly, understand. For salvation to be received, God requires us to  trust in Jesus Christ, God incarnate, as the Savior. For salvation to be  received, God does not require complete adherence to every precept of  sound biblical theology. No, full understanding and agreement with all  aspects of Trinitarianism is not required for salvation.
We strongly hold that Trinitarianism is a biblically-based doctrine. We  dogmatically proclaim that understanding and believing in biblical  Trinitarianism is crucially important to understanding God, salvation,  and the ongoing work of God in the lives of believers. At the same time,  there have been godly men, genuine followers of Christ, who have had  some disagreements with aspects of Trinitarianism. It is important to  remember that we are not saved by having perfect doctrine. We are saved  by trusting in our perfect Savior (John 3:16).  Do we have to believe in some aspects of Trinitarianism to be saved?  Yes. Do we have to fully agree with all areas of Trinitarianism to be  saved? No.