Psalm 99 is described as an enthronement psalm, a song of praise exulting the kingship of God. What strikes me about the psalm is the repeated refrain, "He is holy."
Holiness has moral, cultic, and ontological implications. I'd like to focus on the ontological. Specifically, the holiness of God, God's "set apartness," speaks to God's Otherness, God's qualitative difference from creation. Nicholas of Cusa described God as non aliud, God as "not-other." That is, God cannot be "other" than us as a "different sort of thing." Which is why God is often called "Wholly Other," with a capital "O." God is so different that the word "different" doesn't apply. God is so other that the word "other" fails.
Appreciating all this about God was a long time in coming for me. My mind was long poisoned by that literalness frequently found among atheists. But once the insight arrived beaome a touchstone in both my devotional life and theological thinking.
A breakthrough moment for me came in reading The Divine Names by Pseudo-Dionysius the Areopagite. Writing in the 5th or 6th centuries, Pseudo-Dionysius creates in The Divine Names, along with his other works, a fusion between Neoplatonic philosophy and Christianity. In doing so, Pseudo-Dionysius becomes one of the great theologians of the apophatic and mystical tradition, what some call the Via Negativa of theology.
