What is the content of God's promise to believers?

The content of God's promise to believers is encapsulated in the provision of eternal life and the assurance of salvation. According to Titus 1:2, this promise of eternal life was established before the world began, signifying its everlasting nature. Moreover, in Ephesians 3:6, we're reminded that Gentiles are also partakers of this promise through the gospel. This promise is unconditional, relying solely on Christ's work and not based on our actions, therefore assuring us of our eternal security as believers.