CCC 485
Profession of Faith›SECTION TWO I. THE CREEDS›CHAPTER TWO I BELIEVE IN JESUS CHRIST, THE ONLY SON OF GOD›Paragraph 2. "CONCEIVED BY THE POWER OF THE HOLY SPIRIT AND BORN OF THE VIRGIN MARY"
The mission of the Holy Spirit is always conjoined and ordered to that of the Son. The Holy Spirit, "the Lord, the giver of Life", is sent to sanctify the womb of the Virgin Mary and divinely fecundate it, causing her to conceive the eternal Son of the Father in a humanity drawn from her own.