What is the Church?
The concept of Church being a sign and instrument of the communion of God and men was, as a non-Catholic Christian, difficult for me to grasp. I was taught that the church was an invisible, amorphous structure and came to think of it as an "add on" to the simple Gospel message Jesus brought. In other words, my concept was that the church was a man-made structure that Jesus reluctantly had to allow; a "well, if you must have, then go ahead, but " mentality.
Many of the non-Catholics coming from my particular background had a high degree of suspicion for anything that had structure or hierarchy to it, or remotely resembled Ye Church of Olden Tymes (AKA Catholic Church). Part of this was due to our lack of teaching regarding the early church and from where it derived it's structure and function. As the Catechism below illustrates, the "ecclesia" was used in the OT to describe the gathering of God's people. Complete it was with a hierarchy, officiating priests offering a sacrifice, and a liturgy. Jesus came not to abolish the law, but fulfill it. Why wouldn't the New Testament *ecclesia* have similar structure? My previous view that the NT Church should be a spontaneous gathering of Christians with no specified format or structure, invisible to the world was not consistent with the actual records of salvation history from Old to New Testament and beyond.
Catholics believe that Jesus gave us the Church to be the vehicle, if you will, to bring salvation to the world. Catholics don't separate Jesus from the Church the way I did as a non-Catholic. To be Catholic, one must understand salvation and the gospel in relation to the Church and not separated from it. Jesus is the head and can't be separated from the body, but actually that's what I was doing. My idea of the church was actually a disembodiment of Jesus. I wanted Jesus, but didn't want His church. I just didn't realize that He never intended to be separated from his body.
From the Catechism of the Catholic Church
751 The word "Church" (Latin ecclesia, from the Greek ek-ka-lein, to "call out of") means a convocation or an assembly. It designates the assemblies of the people, usually for a religious purpose.139 Ekklesia is used frequently in the Greek Old Testament for the assembly of the Chosen People before God, above all for their assembly on Mount Sinai where Israel received the Law and was established by God as his holy people.140 By calling itself "Church," the first community of Christian believers recognized itself as heir to that assembly. In the Church, God is "calling together" his people from all the ends of the earth. The equivalent Greek term Kyriake, from which the English word Church and the German Kirche are derived, means "what belongs to the Lord."
752 In Christian usage, the word "church" designates the liturgical assembly,141 but also the local community142 or the whole universal community of believers.143 These three meanings are inseparable. "The Church" is the People that God gathers in the whole world. She exists in local communities and is made real as a liturgical, above all a Eucharistic, assembly. She draws her life from the word and the Body of Christ and so herself becomes Christ's Body
In Brief: 777 The word "Church" means "convocation." It designates the assembly of those whom God's Word "convokes," i.e., gathers together to form the People of God, and who themselves, nourished with the Body of Christ, become the Body of Christ.
778 The Church is both the means and the goal of God's plan: prefigured in creation, prepared for in the Old Covenant, founded by the words and actions of Jesus Christ, fulfilled by his redeeming cross and his Resurrection, the Church has been manifested as the mystery of salvation by the outpouring of the Holy Spirit. She will be perfected in the glory of heaven as the assembly of all the redeemed of the earth (cf. Rev 14:4).
779 The Church is both visible and spiritual, a hierarchical society and the Mystical Body of Christ. She is one, yet formed of two components, human and divine. That is her mystery, which only faith can accept.