Very often we reduce the Holy Spirit to a mere modus, strictly to a function. For example, we hear and say things like, "the Holy Spirit is the mode of Christ's resurrection presence among us." Now, this is a correct assertion, especially when we think of the sacraments as being the works of the Holy Spirit. Hans Urs Von Balthasar stated the matter this way:
Through Jesus of Nazareth, the real man of flesh and blood, God himself becomes definitively concrete. By the uniqueness of Jesus' existence and his transcendent destiny in the Resurrection, we not only learn to know who and what God is but, in our own existence, we become partakers of him'How do we become partakers of Christ? According to Balthasar, it is by receiving "his Spirit who alone can fathom the depth of the Godhead."
So, Balthasar goes on to note, the Holy Spirit "does not merely perform before us the drama of his eternal love, he makes us participate in that drama." St. Paul tells us that the Holy Spirit pours his love into our hearts. The way the Spirit is poured is the Eucharist. After all, are not the bread and the wine transformed into the Christ's Body and Blood by the power of the Holy Spirit, which we then receive? In the words of Aaron Riches, the elect are "[d]rawn into the Church to feed on Christ in the Sacrament of the Altar." Hence, "the pedgogy of the faithful becomes the ontological transformation of eucharistic participation, the 'mysterious continuity linking the Incarnation to the Church.'" Thus, it is precisely in and through the Eucharist that the Church is given and becomes in fact the Body of Christ. This is the work of the Holy Spirit.
Let me conclude this by turning again to Balthasar: "The Spirit...is the one who reveals the eschatological fulfillment toward which all human striving and endeavor are directed."