I was posed with a two-pronged question earlier this week, one that deserved the most thoughtful answers possible as the question has eternal weight. What is the mission of the Church and what is the greatest hindrance to this mission's completion? Now, onto the more fuller answer to prong one.
The mission of the Church in its most essential form is to reflect the Glory of the Godhead, as well as bring glory to its Head, Christ Jesus. Our mission whether we would be Anglican, Roman, Eastern, Baptistic, (any of us who name Christ as Lord) is to live, move and breathe in such a way the the radiant and invisible Glory shines out to the world around us. Its a mission of lifting the Godhead high daily in a world that can be at its best indifferent to the Divine, and overtly hostile at its worst. Its a mission that is both individual and communal at once.
Our success in carrying out this mission has been extremely variable in the two millennia since receiving our marching orders. At times this radiance was blinding as saints stood in arenas, signing their testimonies in their own blood and torn flesh. Sometimes this radiance was eclipsed by our own folly of walling ourselves off from the greater world or exchanging the gold of Scripture for the pyrite of speculation and fable. Yet when God's people came to Him broken and contrite, He would restore them and His radiance would shine again like the sun.
I see three streams, as presented by Scripture as the primary means of accomplishing this mission objective: proclamation, presentation, and preparation.
The Church has been called to proclaim the Word of God. The church hasn't been called to be the herald of "social justice", preach equality (gender, sexual, or otherwise), political viewpoints (left or right), prosperity, financial freedom or anything of the sort. When this occurs, we reduce ourselves to a reflection of the world around us; one thats neither salty or bright. Rather, we're mandated to proclaim the reality of a eternal and holy Godhead, a fallen and corrupt humanity, the inexorable collision course that each are on, and the reconciliation offered by the satisfactorily atoning death of God the Son (Jesus).
The Church has been called to lift the Sacraments of our Christ, Baptism and the Eucharist. These sacraments are far more critical than we may realize. We were, in the creation, made to be primarily both visual and tactile learners. Though there is a significant degree of learning through hearing (ergo the "proclamation" of the word), the bulk of what we're come to understand came from a hands-on or eyes-on moment (e.g. We may have repeated mom's warning of a hot stove by rote, but didn't actually learn until our fingers were singed). In these Sacraments, we see the mysteries of our faith represented in an outward and visible form. We see the cleansing that is received when a life is yielded and brought under the submission of Christ. We see elements poured out and torn like the Divine body that was bad a propitiation for our sins.
Finally, there is the mandate for the Church to Equip her saints. In this equipping, the saints are given the message and tools to become change agents in their worlds. This equipping occurs through the execution of proclamation and presentation. The equipped saint is a spiritually empowered saint, one who is able to impact their circle of the world with the radically transforming power of the Gospel of our Christ.