How do we know faith and repentance are true doctrines?

The doctrines of faith and repentance are validated through scriptural teaching and their evident work in a believer's life. As Paul stated, both are granted as gifts from God, emphasizing that they are not a product of human effort or merit. Ephesians 2:8 reminds us that salvation is by grace through faith, and this faith is itself a gift from God. Moreover, as we see in Romans 4:5, true faith is accompanied by the realization that our works can't save us, which leads to true repentance. When we recognize the character of God and our inherent sinfulness, it generates both a turning away from sin and a reliance solely upon Christ for salvation.