Come, Holy Spirit

From the Office of Readings in the Breviary - St. Irenaeus on Pentecost:

Like dry flour, which cannot become one lump of dough, one loaf of bread, without moisture, we who are many could not become one in Christ Jesus without the water that comes down from heaven.  And like parched ground, which yields no harvest unless it receives moisture, we who were once like a waterless tree could never have lived and borne fruit without this abundant rainfall from above...If we are not to be scorched and made unfruitful, we need the dew of God.  Since we have our accuser, we need an Advocate as well.  And so the Lord in his pity for man, who had fallen into the hands of brigands, having himself bound up his wounds and left for his care two coins bearing the royal image, entrusted him to the Holy Spirit.  Now, through the Spirit, the image and inscription of the Father and the Son have been given to us, and it is our duty to use the coin committed to our charge and make it yield a rich profit for the Lord.