The church at Corinth was the church of God! The church in every place and time is God’s for it was purchased by the blood of Christ (Acts 20:28, Eph. 5:25). Those who make up the church have been sanctified, set apart to God or holy. The term saint is of the same root as sanctify and means “holy one” or one set apart to God from sin. That Paul calls the Corinthians holy is amazing given the problems they had and the sins they committed. But a saint is not a saint because of his lifestyle, but because of God’s call!
As Paul was called by God to be an apostle, every Christian was called by God to be a saint. Those who are called by God to be holy or saints were before the foundation of the world chosen by God to be holy before Him. (Eph. 1:4-5, cf. Rom. 8:28-30) We, as Christians, have been set apart by God. We are holy in His eyes, but God demands that we be holy in our lifestyle. As Peter wrote, “But just as he who called you is holy, so be holy in all you do; 16 for it is written: “Be holy, because I am holy.” (1 Peter 1:15-16)