Many Eastern religions make this claim about God. And now, it is being picked up as a popular idea among Westerners. Unfortunately, it is incoherent.

To say God is unknowable is either a statement about God or a statement about ourselves. If it is a statement about God, it is an affirmation that he has no properties capable of being known. And yet having at least one property is what differentiates existence from non-existence. If God has no properties, then he doesn’t exist.

If it is a statement about ourselves – our ability to know a God with specific properties – then it is self-refuting because the statement itself is a claim to know something about God: He is unknowable. If God were unknowable, we would not even be able to know that He was unknowable. The point can be made succinctly by asking, “How do you know God is unknowable if nothing can be known of God? Isn’t that something you know about him?”

Either way you look at it, that statement is incoherent.