The Communion of Saints is an article of faith
…of the Catholic Church. The term expresses the communion in holy things shared among God’s holy people and the concept of unity and holiness among the baptized Christians in Christ. Saint Paul’s greeting in his letter to the Colossians (1:2) denotes that Christians were generally called saints or “holy ones and faithful brothers in Christ.” They were addressed as holy ones since they were baptized in Jesus Christ the Holy One, saturated with the Spirit of holiness, and adopted as children of God the Father. Their dying in Christ and rising in Him through the waters of baptism sanctified them, and their faith in Jesus the Lord and their decision to pursue Christ made them participants of the holy mystery of God.