It was a phenomenon of the New Testament Church, their experience of the Holy Spirit:
151. The Church as marked and sealed “with Holy Spirit and fire” (Mt 3:11), continues the work of the Messiah, opening the gates of salvation for the believer (cf. 1 Cor 6:11). Paul states it as follows: “you are … a letter of Christ administered by us, written not in ink but by the Spirit of the living God” (2 Cor. 3:3). The same and only Spirit guides and strengthens the Church in the proclamation of the Word, the celebration of faith, and the service of charity, until the Body of Christ attains the stature of its Head (cf. Eph 4:15-16). Thus, through the effective presence of his Spirit, God assures until the parousia his offer of life for men and women of all times and places, pressing forward the transformation of history and its dynamisms. Hence, today the Lord continues to pour out his Life through the work of the Church, which with “the power of the Holy Spirit sent from heaven” (1 Pet 1:12) continues the mission that Jesus Christ received from his Father (cf. Jn 20:21).
Note the lyrical nature of these passages. This isn’t something that can be worked out by reason alone and thus explained. Gates are opened for us; we pass into a new place. Disciples are letters written by God for the benefit of those with whom he is trying to communicate. Liturgy and charity draw us–the Body–to Christ, our Head. Our mission is no less than a transformation of human history.
152. Jesus transmitted to us the words of His Father, and it is the Spirit who keeps the Church mindful of Christ’s words (cf. Jn 14:26). From the beginning, the disciples had been formed by Jesus in the Holy Spirit (cf. Acts 1:2); in the Church, the Spirit is the inner Master who leads to the knowledge of all truth, forming disciples and missionaries. That is why the followers of Jesus should let themselves be constantly guided by the Spirit (cf. Gal. 5:25), and become impassioned for the Father and the Kingdom: proclaiming the Good News to the poor, healing the sick, consoling the sorrowful, freeing the captives, and proclaiming to all the Lord’s year of grace (cf. Lk 4:18-19).
We are nudged, urged, directed to the preaching of Christ. The advent of his public ministry in Luke 4:16-30, the citation of Isaiah, as well as the curiosity, the doubts, and the antagonism are all part of a whole, an inaugural event, if you will that tells us much of what the Lord’s intentions are with regard to us. Not to mention the consequences of all of that.
For deeper examination, an English translation of the 2007 document from the Aparecida Conference.