CAPG's Blog 

Novena for Priests to the Holy Ghost:

"As they cry out with all the faithful, "Abba, Father!" may Your priests be ever more closely identified with You in Your divine Sonship and offer their own lives with You, the one saving Victim.
Make them helpful brothers of one another, and understanding fathers of all Your people. On this Pentecost Sunday, renew in Your priests deeper faith, greater trust in You, childlike reliance on our Mother Mary, and unwavering fidelity to the Holy Father and his bishops.

Holy Mary, intercede for your priests.
St. Joseph, protect them.
St. Michael, defend them.
St. John Vianney, pray for them.
Amen. "

"Pope Leo XIII, May 9, 1897, decreed that a novena to the Holy Ghost should be made every year in preparation for the feast of Pentecost. (...) During this novena no particular form of prayer is of obligation. Any prayer to the Holy Ghost will suffice.

Encyclical of Pope Leo XIII on the Holy Spirit:  Divinum Illud Munus

Novena to the Holy Ghost in Preparation for the Feast of Pentecost: The novena of the Holy Spirit is the chief of all the novenas, because it was the first that was ever celebrated, and that by the holy apostles and the most Holy Mary in the supper room, being distinguished by so many remarkable wonders and gifts; principally by the gift of the same Holy Spirit, a gift merited for us by the passion of Jesus Christ Himself. Jesus Himself made this known to us when He said to His disciples that if He did not die He could not send us the Holy Ghost: "If I go not, the Paraclete will not come to you; but if I go, I will send Him to you" (John xvi. 7). We know well by faith that the Holy Ghost is the love that the Father and the Eternal Word bear one to the other; and therefore the gift of love which the Lord infuses into our souls, and which is the greatest of all gifts, is particularly attributed to the Holy Ghost. As St. Paul says, "The charity of God is poured forth in our hearts by the Holy Ghost, Who is given to us (Rom. v. 5). In this novena, therefore, we must consider, above all, the great value of divine love, in order that we may desire to obtain it, and endeavor, by devout exercises, and especially by prayer, to be made partakers of it, since God has promised it to him who asks for it with humility: Your Father from heaven will give the good Spirit to them that ask Him" (Luke xi. 13).

Prayer to the Holy Spirit for the Church: "O Holy Spirit, our Creator, come to the aid of Thy Holy Church, and strengthen and confirm it by Thy supreme power against the incursions of its enemies; and by Thy love and grace renew the spirit of Thy servants whom Thou hast anointed, so that they may glorify in Thee the Father and His only begotten Son, Jesus Christ our Lord. Amen.”—(Indulg. 100 days. Resc. Aug. 26, 1889.)

Short Prayer to the Holy Ghost : Holy Spirit, Spirit of truth, come into our hearts; give to all peoples the brightness of Thy light, that they may be well-pleasing to Thee in unity of faith. (Indulgence of 100 days, once a day. Leo XIII, July 31, 1897.)

Source: My Prayer Book; Happiness in Goodness: Reflections, Counsels, Prayers and Devotions By Francis Xavier Lasance