Holy Nation is God's description of His redeemed people, set apart to belong to Him, reflect His character, and proclaim His greatness.
In the Old Testament, God called Israel to be a holy nation among the nations of the earth. In the New Testament, Peter applies this covenant language to the church, not to erase the distinction between Israel and the church, but to emphasize that all who are in Christ have been set apart for God's service. As God's holy nation, the church belongs to Him, lives under His authority, and declares His praises before the world. Holiness is therefore not merely personal morality but a covenant identity expressed through a distinct and obedient people.
See in Scripture: Exodus 19:5–6; Deuteronomy 7:6; 1 Peter 2:9–10; Titus 2:14