The giving of the Spirit to the new people of God crowns the mighty acts of the Father in salvation history.

The Jewish feast of Pentecost called all devout Jews to Jerusalem to celebrate their birth as God's chosen people, in the covenant Law given to Moses at Sinai (see Leviticus 23:15-21; Deuteronomy 16:9-11).

In today's First Reading the mysteries prefigured in that feast are fulfilled in the pouring out of the Spirit on Mary and the Apostles (see Acts 1:14).

The Spirit seals the new law and new covenant brought by Jesus, written not on stone tablets but on the hearts of believers, as the prophets promised (see 2 Corinthians 3:2-8; Romans 8:2).

The Spirit is revealed as the life-giving breath of the Father, the Wisdom by which He made all things, as we sing in today's Psalm. In the beginning, the Spirit came as a "mighty wind" sweeping over the face of the earth (see Genesis 1:2). And in the new creation of Pentecost, the Spirit again comes as "a strong, driving wind" to renew the face of the earth.

As God fashioned the first man out of dust and filled him with His Spirit (seeGenesis 2:7), in today's Gospel we see the New Adam become a life-giving Spirit, breathing new life into the Apostles (see 1 Corinthians 15:45,47).

Like a river of living water, for all ages He will pour out His Spirit on His body, the Church, as we hear in today's Epistle (see also John 7:37-39).

We receive that Spirit in the sacraments, being made a "new creation" in Baptism (see 2 Corinthians 5:17; Galatians 6:15). Drinking of the one Spirit in the Eucharist (see 1 Corinthians 10:4), we are the first fruits of a new humanity - fashioned from out of every nation under heaven, with no distinctions of wealth or language or race, a people born of the Spirit.