How do we know the gospel of Jesus Christ is true?

The gospel's truth is rooted in the revelation of Jesus Christ as presented in Scripture. As John puts it in Revelation, the revelation of God’s will and purpose is made manifest through the person of Jesus Christ. This truth is further supported by the prophecies spoken throughout the Old Testament that point to Christ’s coming, His ministry, death, and resurrection. The fact that Christ willingly fulfilled His role as the Lamb that was slain, and the corresponding assurance of redemption through faith, validate the reliability of the gospel message, proclaiming God's faithfulness to His promises.