How do we know that everlasting life is a true promise?

The assurance of everlasting life comes directly from the authority of Christ. In John 5:24, Jesus proclaims that whoever hears His word and believes in the one who sent Him has eternal life. This statement is backed by the very nature of Christ as the Word of God, who possesses all authority in heaven and earth. Moreover, Romans 10:17 clarifies that faith comes from hearing, and hearing through the word of Christ, reinforcing the truth of this promise. Therefore, believing in Christ and His words ultimately grounds our hope in the certainty of this grace-filled promise—eternal life is incorporated within the character of God, who is truth.