The answer to this question is no. The Bible does not mention a “Trinity,” let alone state that one must believe in it in order to attain salvation. Furthermore, no verse in Scripture says you must believe that Jesus Christ is God in order to be saved. For further study on the two main verses that some Christians use to support the belief that one must believe in the Trinity in order to be saved, click on the following links: 1 John 2:22 and 1 John 4:1-3.
Ok, what does the Bible say?
That if you confess with your mouth, “Jesus is Lord,” and believe in your heart that God raised him from the dead, you will be saved.
Salvation is of the utmost importance, so let’s be sure we understand God’s instructions, which are really quite simple. To be saved, you must confess with your mouth that Jesus is Lord. What does that mean? It means that you say what the Bible clearly declares—that Jesus is the Son of God who died for your sins, was raised from the dead, and highly exalted to the right hand of God. Have you ever opened your mouth and said, “Jesus is Lord?” Why not say it right now? It’s simple: “Jesus is Lord.”
Romans 10:9 goes on to say that along with confessing that Jesus is Lord, you are to believe in your heart that God raised him from the dead. What is it to believe in your heart? It means to really believe it. Is that difficult? No, not at all. You probably believe that George Washington was the first president of the United States, even though you never saw him. In the same way, there are many, many valid reasons to believe that God raised Jesus up from the dead.
For proof, read our article, “23 Arguments for the Historical Validity of the Resurrection of Jesus Christ.”
Once you have confessed with your mouth that Jesus is Lord and believed in your heart that God raised him from the dead, you are saved. Salvation is very easy because God wants all men to be saved (1 Tim. 2:4), and He is offering it as a free gift. The reason it is free to you is because Jesus Christ paid the price for it with his life.