Catechesis Pro Advltioribvs Scripta, De his potissimum capitibus

I. Explain this to me more significantly. R. Although one must simply believe the word of God here, and divine things cannot be referred to us properly and exactly by human parables, I will try to say something. In the Sun, which is only one, certain things are nevertheless found that are distinct, and so distinct that one is not the other, yet that distinction does not destroy the unity of the Sun, or establish more Suns. For in the Sun, the globe or the body itself is seen, from which light arises or splendor is poured as if from a fountain, and heat emanates from both. Nor are these confused among themselves, so that splendor is the same thing as heat: nor do the distinct things make more Suns, but the globe, splendor, and heat, these three are one Sun. In the same manner, the eternal Son is generated from the eternal Father, and the Holy Spirit proceeds from both: and the Father is not the Son, nor is this Holy Spirit, but the Father is the Father of the Son, and the Son is the Son of the Father, and the Holy Spirit is the Spirit of the Father and of the Son; nevertheless, these three are one, true, and eternal God, of the same nature and divine essence, majesty, and power.