How can the idea of the Trinity be reconciled with God’s simplicity? Even if one says that the Trinity is not three different entities, just three different aspects of the
one God, to have three aspects is not simple.
Or is this yet another “mystery”, instead of a contradiction?
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The number of contradictions masquerading as “mysteries” is getting uncomfortable large.
There’s another thread on this matter.
Check it out.
My comments from the beginning of that thread:
"God’s nature is indivisible. This is the principle of divine simplicity - the transcendent divine essence, whatever it is, must be without parts.
"But the dogma of the Holy Trinity doesn’t contradict this. Indeed, it asserts that God’s essence is singular, indivisible, simple. It’s just that it mutually indwells three eternal Persons - the Father, the Son whom the Father eternally begets, and the Spirit who proceeds eternally from the Father (and, in western theology, from the Son, but I’m not touching that).
“I know it’s complicated - and we certainly all understand it far less than we think we do. But the indivisibility/simplicity/distinction-less quality of God’s nature applies, as it says, to God’s nature. The Persons who share that eternal nature are distinct.”
Also, remember that each Person of the Holy Trinity is NOT a “part” of God or an “aspect” of God. That’s not really accurate. Each person is fully God.
The Father - a distinct Person - is fully God.
The Son - a distinct Person - is fully God.
The Spirit - a distinct Person - is fully God.
God’s essence is without parts / not composite, and only one divine essence exists or could ever exist. Three eternally existing Hypostases share it.