The mission of Christ and the Holy Spirit is brought to completion in the church, as the church has no light other than Christ's. The establishment of the church in the catechism is based on the belief in Christ Jesus and his mission being inseparable.
Father Mike Schmitz introduces the Catechism in a Year podcast, where listeners can learn about God's plan and the Catholic faith.
The church's beliefs about Christ are the foundation of everything they believe about the church, including that the mission of Christ and the Holy Spirit is brought to completion in the church. The church is characterized as holy, catholic, one, and apostolic.