“The Word is, by definition, immanent in the divinity and active in the world, and as such the Father’s revelation. A revelation of the Father without the Logos and his incarnation would be like speaking without words.”
― Karl Rahner, The Trinity
“The mystery of the Holy Trinity is the most fundamental of our faith. On it everything else depends and from it everything else derives. Hence the Church’s constant concern to safeguard the revealed truth that God is One in nature and Three in Persons.”
—FATHER JOHN A. HARDON, S.J
“The Father is from no one; the Son is from the Father only; and the Holy Spirit is from both the Father and the Son equally. God has no beginning; He always is, and always will be. The Father is the progenitor, the Son is the begotten, the Holy Spirit is proceeding. They are all one substance, equally great, equally all-powerful, equally eternal.”
–Fourth Lateran Council, 1215
“The Father is entirely in the Son and entirely in the Holy Spirit; the Son is entirely in the Father and entirely in the Holy Spirit; the Holy Spirit is entirely in the Father and entirely in the Son. None of the persons precedes any of the others in eternity, nor does any have greater immensity or greater power. From eternity, without beginning, the Son is from the Father; and from eternity and without beginning, the Holy Spirit has proceeded from the Father and the Son.”
–The Council of Florence, 1439
The Father, Who is Justice, is not without the Son or the Holy Spirit; and the Holy Spirit, Who kindles the heart of the faithful, is not without the Father and the Son; and the Son, Who is the plenitude of fruition, is not without the Father or the Holy Spirit; they are inseparable in Divine Majesty.
-Hildegard of Bingen