Roman Catechism 10.5

Chapter 10 — Part I: The Creed — Article VIII: I Believe in the Holy Ghost

Section 5. The pastor, then, should teach that by the words Holy Ghost in this Article is understood the Third Person of the Blessed Trinity, a sense in which they are used, sometimes in the Old, and frequently in the New Testament. Thus David prays: Take not thy Holy Spirit from me; and in the Book of Wisdom we read: Who shall know thy thoughts, except thou give wisdom, and send thy Holy Spirit from above? And in another place it is said: He created her in the Holy Ghost.' We are also commanded, in the New Testament to be baptised in the name of the Father, and of the Son, and of the Holy Ghost. We read that the most holy Virgin conceived of the Holy Ghost; and we are sent by St. John to Christ, who baptizeth us in the Holy Ghost.' There are many other passages in which the words Holy Ghost occur.