What does it mean to be declared righteous according to the Bible?

The notion of being declared righteous is crucial in Reformed theology, as expressed in 2 Corinthians 5:21, which states that God made Christ to be sin for us, so we might be made the righteousness of God in Him. This exchange illustrates the doctrine of justification, highlighting that believers are not righteous by their own works but through the imputed righteousness of Christ, granted through faith. Such a declaration grants peace and safety, as individuals now stand justified before a holy God.