I will try to explain the meaning of the church depending on the essential role of the Trinity; Father, Son, and Holy Spirit. I have depended on a number of paragraphs in the book of the Catechism of the Catholic Church (758-769, 781-801).
I- Symbols of the church from the Old Testament
The church, which has been established by our Lord Jesus Christ, has a Trinitarian symbol in the Old Testament. This is because she has an origin in the plan of the Holy Trinity (CCC758). The three visitors, who appeared to Abraham and promised him that his wife Sarah will have a son (Gen 18) (CCC761) were symbol of the Trinity who will be with the people of God forever.
The goal of Jesus Christ to His people through the Church is to share in the divine life of the eternal Father. This life needs the Holy Spirit who glorifies the Church when Christ comes again. Church is like yeast, or a seed (CCC767), or a little flock in the world, have a mission to proclaim the kingdom of God to all nations. God’s people have special characteristics, so they are distinguished from the world. Every one want to be a member of this church must be born again of water and of the spirit.
II- Trinity in the Holy Prayer
When Jesus Christ taught His disciples the Holy Prayer, He demands us knowing that God is our Father by the Holy Spirit power. By Jesus Christ, His Son, we also, and by the adoption of the Holy Spirit, become His sons and daughters. This filiation will not come to exist without remaining in Jesus. Remaining branches in the vine is a symbol of that (John 15: 4-5) (CCC787). This abiding is through the Holy Spirit, who Jesus has promised the church, His bride.
III- The Pentecost
Fifty days after the Crucifixion, Church has been brought to the world when the twelve disciples were all together in one place and were filled with the Holy Spirit (CCC767). The Holy Spirit bestowed upon them the spiritual gifts to present glory with Jesus, to the Father (CCC799).
Believers are able to become people of God only when they born by the Holy Spirit as Christ faithful; Christ is the head and leader of the Church (CCC792, Col 1: 18). This is same as the head of the human body; it should be a temple for the Holy Spirit (CCC790). Jesus Christ and the church are one, and the Holy Spirit makes the church the Temple of lively God. The Holy Spirit is the principle of every real action in this body (the body of the church). One can practice this through the Sacraments, virtues, and the charismatic gifts (CCC798). All the gifts are from the Holy Spirit in order to glorify the Father in our life.
Love is the base of the relationship between God the Father and Jesus Christ, head of the Church. So we have to love Jesus because he first loved us as the apostle John said (1John 4: 19). This love is a fruit of the work of the Holy Spirit in our hearts (CCC798). It makes us a priestly nation, Father’s Priests.
By this love, members of a church become one with Jesus Christ since He is the High priest and they should also be a holy priesthood as St. Peter said in his letter (1p 2: 5). The mutual love between any bridegroom and bride is a symbol for the mutual love between Jesus Christ as the Bridegroom and the Church as the Bride (CCC789 & 796). There is no life to any local church without having love which is her breath; I mean the presence of the Holy Spirit, same as the presence of love between the soul and the body in any human being.
Sun as a star sends its light full of energy to support almost all life. We can use the concept of standard to explain a bit little about Trinity; suppose the sun is a symbol for the Father, its light, the Son Jesus, and its energy, the Holy Spirit.
We have seen that how the Holy Trinity (our Father, Jesus our brother, and the Holy Spirit who live life of love inside our hearts) is encountering us, people of God, through the Holy Church forever.
Fr (Archbishop) Habib Jajou