Consider the opening to Paul’s Letter to the Romans. Does this sound pluralistic to you?
Paul: “The gospel was promised beforehand by the prophets of Scripture. The gospel concerns God's Son, Christ Jesus. He was bodily descended from David. He was declared to be God's Son by the Holy Spirit, by means of the resurrection. He is the Lord. He is the mediator of God's grace. He wants all nations to obey God by coming to faith in Him.”
Notice the hard, exclusive character of the Gospel, and how it denies other claims.
It's the gospel, not a gospel. There are no other “good newses” (vs Unitarianism).
Only onescripture is the Holy Scripture. No other religious book is from God.
Christ is the Son of God. Jesus was not a prophet, contra Islam.
Christ came from David's line, so no one can just claim to the be the Messiah without being forced to prove it.
Jesus is the same person as “the Christ.” A “Christ-spirit” did not come down on an ordinary man (vs the Jehovah’s Witnesses).
Christ alone is Lord (vs Mormonism).
He alone mediates God's grace. (no grace comes to us from Mary or the saints. How could it? They aren’t God).
All must come to faith in Him. There are not many paths to heaven, there is only one.
At Christmastime, remember that Jesus Christ claimed to be God’s Son, the only Savior, and the men He appointed all preached that Christianity alone was the one true faith.