27. We have sufficiently spoken of the Father and of the Son, so far as was possible for us to see through this glass and in this enigma. We must now treat of the Holy Spirit, so far as by God’s gift it is permitted to see Him. And the Holy Spirit, according to the Holy Scriptures, is neither of the Father alone, nor of the Son alone, but of both; and so intimates to us a mutual love, wherewith the Father and the Son reciprocally love one another. But the language of the Word of God, in order to exercise us, has caused those things to be sought into with the greater zeal, which do not lie on the surface, but are to be scrutinized in hidden depths, and to be drawn out from thence. The Scriptures, accordingly, have not said, The Holy Spirit is Love. If they had said so, they would have done away with no small part of this inquiry. But they have said, “God is love;” so that it is uncertain and remains to be inquired whether God the Father is love, or God the Son, or God the Holy Ghost, or the Trinity itself which is God. For we are not going to say that God is called Love because love itself is a substance worthy of the name of God, but because it is a gift of God, as it is said to God, “Thou art my patience.” For this is not said because our patience is God’s substance, but in that He Himself gives it to us; as it is elsewhere read, “Since from Him is my patience.” For the usage of words itself in Scripture sufficiently refutes this interpretation; for “Thou art my patience” is of the same kind as “Thou, Lord, art my hope,” and “The Lord my God is my mercy,” and many like texts. And it is not said, O Lord my love, or, Thou art my love, or, God my love; but it is said thus, “God is love,” as it is said, “God is a Spirit.” And he who does not discern this, must ask understanding from the Lord, not an explanation from us; for we cannot say anything more clearly.
Complete source paragraph · On the Holy Trinity, Chapter 17.—How the Holy Spirit is Called Love, and Whether He Alone is So Called. That the Holy Spirit is in the Scriptures Properly Called by the Name of Love.; original source section: Chapter 17, source paragraph 2 · Original source