Christ was conceived by the Virgin Mary through the power of the Holy Spirit (Matthew 1:18 and Luke 1:35). He descended on Christ in the form of a dove when He was baptized on the river Jordan (Matthew 3:16). After His Resurrection, Christ poured out the Spirit upon the apostles (John 20:22), making them sharers in His own mission (John 20:21). The Holy Spirit descended on the apostles gathered in prayer with Mary on the day of Pentecost (Acts 2:1-4) and stirred the apostles to the mission of proclaiming the Good News to all peoples. Christ continues active in His Church through the Holy Spirit.
The Fathers of the Church acknowledged the Holy Spirit played a vital role in the Mass, particularly in the consecration. The Holy Spirit sanctifies and transforms whatever He touches. “The Holy Spirit consecrates the bread and the wine, and gathers the faithful ‘into one body’ along with Christ and makes them a spiritual offering pleasing to the Father,” said Saint John Chrysostom.
After Pentecost, the apostles and their followers converted and baptized, “devoted themselves to the breaking of bread and the prayers.” (Acts 2:42) The Encyclical Dominum et Vivificantem stated: “Guided by the Holy Spirit, the Church from the beginning expressed and confirmed her identity through the Eucharist … The Holy Spirit is present and active in the sacrifice of Christ … In His humanity, Christ opens Himself to this action … Through the Eucharist, individuals and communities, by the action of the Holy Spirit, discover the divine sense of human life.”
The primitive Church was a community founded on the teaching of the apostles (Acts 2:42). It was completely animated by the Holy Spirit, who enlightened the believers to understand the Word, and gathered them in charity around the Eucharist. The Church grew into a multitude of believers who “were of one heart and soul.” (Acts 4:32)