These words about the Holy Spirit, from the Nicene Creed, ring through our memory and won't go away:

who proceeds from the Father and the Son, who with the Father and the Son is adored and glorified

The phrase "and the son" (often referred to as the Filioque) has been the object of vigorous discussion. (See footnote.) One can go round and round on this issue, but there's an underlying difficulty: the inadequacy of language itself. But it's not language that's the problem; it's the necessarily incomplete, stunted way we apes see the world around and within us.

Our Buddhist brothers and sisters see the problem, and address it in the koan: "If you meet the Buddha on the road, kill him." This koan makes no "sense" in a conventional way, but hints at reality by turning language upside down. Poetry tries to move beyond language to a deeper reality. But poetry is too weak to finish the job. Paradox, or something like it, is necessary. We need to take a crowbar and bend language beyond recognition.

So the question of the Filioque is only a tiny part of a much larger question: does God exist? This is actually a trick question. We can't say Yes, because our notion of existence limits God. But we can't say No, either, because the very question puts the idea of God in a limiting box. What to do? We can respond to both the Yes people and the No people with a sparkle in the eye and say to each, "Oh, baby, you have no idea!"

So where do we go? Jesus, God incarnate, steers us in the right direction. We could do worse than to adopt this Western koan (see footnote):

There is no God, and Mary is his mother.

That's as good an approach as any. It makes no sense, and is not supposed to make sense. It makes us aware, though, of the way that God can shine through. (But "shine through" already leans on our limited approach to reality, as does even the word "can".) God shines through? Yes, by way of Immanuel, God with us.

Is this heretical? No, and it's not even heterodox. "But wait a minute," one might say. "The Nicene Creed speaks of the Son as consubstantial (one in being) with the Father. So God must exist."

Not so fast. Let's look at a seemingly unrelated passage: Genesis 1:16 ...

God made the two great lights, the greater to govern the day, and the lesser one to govern the night.

... and Isaiah 10:26 ...

The light of the moon will be like that of the sun and the light of the sun will be seven times greater.

... and Ezekiel 32:7 ...

When I snuff you out I will cover the heavens, and all their stars will I darken; the sun I will cover with clouds and the moon shall not give its light.

... and Mark 13:24: ...

But in those days after that tribulation the sun will be darkened, and the moon will not give its light.

There are literalists (or, specifically, creationist) individuals who argue from this that the moon gives intrinsic light, not reflected from the sun. These four passages (and there are others) are not intended to be astronomical texts; they serve other purposes.

Considering, then, the Nicene Creed phrase "consubstantial with the Father". That phrase does not address the question of existence, but rather the relationship between the Father and the Son, and only that. There you go.

(There's even a book There Is No God, and Mary Is His Mother. While it's intriguing and a fun read, it's riddled with logical flaws, and certainly doesn't help with the underlying issue of language and our experience of the world around and within us.)

Any attempt to define God with language, using our limited conceptual framework, is doomed. Yet we must also avoid an attitude of flippancy toward these questions. We must remove the sandals from our feet; the ground we stand on is holy ground.

Footnotes:

Go to youtube and search for Filioque. You'll see Eastern Orthodox voices, for example, labeling the Filioque as heresy. You'll see Catholic voices saying otherwise. Thomas Aquinas, of course, has much to say. The wikipedia article on the Filioque does a thorough but dense job of untangling the issues. It notes that although Eastern Catholics are bound to accept the Filioque as a matter of faith, they don't actually mention it when they recite the creed! And some corners of Western Christianity (for sample, the Episcopal Church in the United States) seem to be moving toward dropping the Filioque.

"There is no God, and Mary is his mother" has been attributed to George Santayana, but there's no evidence that he actually said it. It appears in a poem by Robert Lowell, which approaches Santayana's tortured relationship with the Catholic Church.