How do we know that Christ's salvation is true?

The truth of Christ's salvation is confirmed by His resurrection from the dead, which proves that God accepted His sacrifice for sin. In Isaiah 53:4-5, it is foretold that the Messiah would bear the sins and iniquities of His people, achieving reconciliation with God. The apostolic testimony asserts that belief in Christ guarantees eternal life, as stated in John 3:36; one who puts their faith in Him is given the assurance that they are saved. Thus, Christ's work stands as the only foundation for a believer's hope and security.