What does the Bible say about being saints in Christ?

The term 'saints in Christ Jesus' reflects a profound spiritual reality, where believers are set apart by God unto Himself. As seen in Philippians 1:1, saints are not merely defined by their actions but by their union with Christ. This separation signifies a definitive work of God, which aligns with Ephesians 2:4-5, where the rich mercy and love of God brings us from spiritual death to life together with Christ. The core of being a saint is being made holy by God—holiness in this context is not incremental but given fully in Christ. Thus, saints are seen as belonging to a royal priesthood and a holy nation, called to proclaim His praises as conveyed in 1 Peter 2:9.