We cannot know by means other than revelation the three persons of the Trinity. Jesus was the revelation of the Father and further processing from them both was the Holy Spirit. The discussion then on the persons of the Trinity are within our deep seeded desire to know and understand the truth, a part of our very nature. So it is quite fitting that we discuss God in His nature and persons so long as they are discussed with correct terms non-conflicting ideas. Five of these are unbegotten, paternal, filial, spiration, and procession. The debate on these terms can continue without necessary heresy as long as they do not conflict with the laid out notions while knowing they are consequent to faith, which would then be heretical.

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