To the seraphim who surround God’s throne, the outstanding characteristic of God that they ceaselessly proclaim is His holiness, pointing to the fact that God is in His essence an impenetrable mystery. That is objectively, metaphysically, and ontologically the absolute truth about God.
But it is not who God is to us.
When Moses asked to see God’s glory, God told him he wouldn’t be able to survive it. But God told Moses He would put him in a cleft in a rock and hide him as His glory passed by, and that as He passed, He would proclaim His name to Moses. In Hebrew, names were believed to reveal nature, and so God was proclaiming His nature to Moses and in the process revealing who He is to the Israelites.
What did He say?
The LORD passed before him and proclaimed, “The LORD, the LORD, a God merciful and gracious, slow to anger, and abounding in steadfast love and faithfulness, keeping steadfast love for thousands, forgiving iniquity and transgression and sin, but who will by no means clear the guilty, visiting the iniquity of the fathers on the children and the children’s children, to the third and the fourth generation.” (Ex. 34:6-7)
In His essence, God is unknowable and holy; to us, however, God’s nature is to be merciful and gracious. What He wants us to know about Him is His patience, His steadfast love and faithfulness, and his forgiveness. For humanity, that is who He declares Himself to be.
He remains holy, however, which means that He must judge the guilty. While God spends most of His self-revelation on His graciousness, mercy, and forgiveness, this needs to be balanced with a recognition that judgment is also part of His character.
The fact that God reveals Himself means that although He is beyond our ability to know or understand, there are things about Him that we can know. God accommodates His revelations to us to what we need to know about Him and to our ability to understand. Focusing on divine revelation and affirmations of what we can know about Him is called cataphatic theology, in contrast to anaphatic theology which emphasizes the limits of our understanding and focuses on what God is not.
The Eastern Orthodox churches tend to emphasize anaphatic theology (God as mystery) while acknowledging that cataphatic theology has its place; the Reformed along with much of modern evangelicalism emphasize the cataphatic (God as revealed) almost entirely, with at best a nod of the head toward anaphatic theology; the Roman Catholic Church argues that anaphatic and cataphatic theologies complement and balance each other.
Although I am a Reformed evangelical, I lean toward the Orthodox outlook here. I certainly believe that it is important to study revelation and to do our best to understand it, but I also think we need more epistemological humility when we do theology, recognizing the limits of our ability to understand the God whom even the seraphim see as a mystery. The deeper I go into the Bible, the more I recognize that He is a mystery beyond what I can understand.
And recognizing that should make us more willing to work with those whose theologies differ from ours on some points, since it is certain that there is far more to God than our theological systems recognize. It should also make us far more careful about limiting the way God works and what faithfully following Him looks like beyond what is expressly taught in Scripture.