How do we know that believers are made new in Christ?

In Ephesians 4:24, Paul teaches that believers are to put on the new man, which is created in righteousness and holiness. This transformation is a result of divine regeneration imparting a new nature that is in harmony with God's character. Peter further echoes this truth when he states that believers partake of a divine nature through God's precious promises. The old sinful nature remains, but it does not control the believer's actions. Instead, it is the new nature that resides in the believer, identified with Christ's righteousness, which allows them to approach God with confidence.