44. They say that, according to certain passages in the Word in the external sense, it is not permitted to enter with the understanding into the things concerning the Trinity. While this faith reigns, and is ratified and confirmed, then there is no room in the understanding for enlightenment. Such a faith closes the way of access for the light and indeed for the understanding of the Word in the spiritual sense. Yet if it is believed that the Divine is only in the Lord, then the understanding can be enlightened from many passages in the Word, which passages are not otherwise seen or understood, as for example, that the Lord is one with the Father, and many other examples.
I have heard certain spirits reasoning about three persons and yet one God, and they reasoned from the words there [The Athanasian Creed], that they are one substance or essence and thus that the three are one, or, as is there said, that there is a trinity in unity, and a unity in trinity, thus believing that still there is one Divine. By that reasoning they confirmed themselves with the lips that they are one trine and so that it is scarcely a unanimous trine. It was then said to them that they are able to say these things and to persuade others who only pay attention to words that such is the case. But it was said to them, "Think of one of three persons, each one of whom is God," then they were asked whether, from that thought, they were able to say or affirm one God, but they could not. It was thence evident that those were only words, but that each one thought in no other way than of three Gods. It was further said that such things are in the Athanasian faith, because in no other way could they connect the one with the other, knowing from interior thought and also from the Word, that God is one, consequently but one Person.