1 Corinthians 1:1-3
1 “Paul, called as an apostle of Jesus Christ by the will of God, and our brother Sosthenes, 2 To the church of God which is in Corinth, to those who have been sanctified in Christ Jesus, saints by calling, with all who in every place call on the name of our Lord Jesus Christ, their Lord and ours: 3 Grace to you and peace from God our Father and the Lord Jesus Christ.”
Have been sanctified: Paul speaks of a past-tense event of sanctification. This sanctification occurred at the moment of salvation. When we believe in Christ we are sanctified, set apart, for God to the core. Paul does not speak here of an ongoing or progressive sanctification in which believers are slowly being made righteous. To the contrary, according to Paul, believers are righteous to the core upon faith in Jesus. So, while behavior is still being sanctified, we as believers are righteous to the core.
Their Lord and ours: Paul is referencing the election of Jews and Gentiles to salvation. The church at Corinth was elected for salvation and therefore was to be considered equal with Israelite converts. God has chosen the world for salvation through the offer of the Gospel. This universal election demolishes any racial divide existent between Jew and Gentile (see also Galatians 3:28).
Grace to you and peace: God has nothing but grace and peace for the world. In Christ, God has poured out His grace and made His peace offering. All who believe in this are saved and consequently experience God’s empowering grace and a peaceful relationship with God.