The paradox in theology proper is that one the one hand, God is truly unfathomable. There is no way a finite, time-bound being can truly know a God who is infinite, eternal, and unchangeable.
And yet, God clearly intends for humanity to know God, otherwise why would he reveal himself?
And you know this to be true if you think about it. God made humanity in his image. So when he tells us what he is like we ought to be able to understand. To reiterate, I’m not saying we can totally fathom him, because he is God and we are not, but we ought at least to be able to understand him.
You can see this hinted at in The Westminster Shorter Catechism. Question 4 says, “Q. What is God? A. God is a Spirit, infinite, eternal, and unchangeable, in his being, wisdom, power, holiness, justice, goodness, and truth.” The seven attributes listed are possessed by human beings, even in their natural state, in flawed form (though we might have to look for evidence of them). They constitute part of the image of God in us and reflect our Creator. But we do no possess, even in a regenerated state, these attributes to the degree God does, that is infinitely, eternally, and unchangeably.
So God speaks and he shows (to steal from Carl Henry) and God wants us to understand what he is saying and showing because he wants us to know him. He has wanted this from the beginning and so he has always, especially significant points in salvation-history, revealed himself to humanity.
Humanity doesn’t always hear him or, more likely, humanity often refuses to hear him when he speaks or recognize him when he acts.
Hebrews 1:1-3 makes clear that God has continued to speak and show through the Son, the Living Word of God. This God who speaks and shows Has spoken to us through His Son and has shown us who he is by that same Son. The Son is the best revelation of God to us. As the living Word of God, Jesus has revealed God in ways that previous words spoken cannot. As the Anointed Son of God he has acted in ways that far surpass any previous actions on God’s part.
He speaks the truth of God to us and shows us what God is like, specifically, the depth of God’s love, the wideness of his mercy, and the fullness of his grace.