Nām aṟiyōm. We know not. There's a scandal hidden in it. Here is a man his disciples called a knower of Śiva, a satguru, someone who had seen clean through to the ground of being — and the wisdom he hands down is not "I have found the Truth" but we know not. The knower ends not in a claim but in a confession. And that confession is the whole teaching.
Because the Real he touched — Paraśiva, the That beyond mind and name, the one you only ever approach by neti neti, not this, not this — was never something he could know the way you know a fact or a face. Knowing means a knower standing apart from a thing and grasping it. But the Self is not apart from you; it is the very one doing the looking. The eye cannot turn and see itself. So at the summit, knowing has nothing left to seize and simply falls silent. "We know not" is not the ignorance that sits below knowledge — it is the silence that opens above it, where every concept you carried has burned away and existence is made luminous and strange again, no longer flattened into the merely "known."
This is why it is the hardest saying to fake and the most freeing to receive. Notice he does not even say I know not. He says we. The little self that collects teachings and announces "now I understand Shaivism, now I have grasped God" is precisely what dissolves — there is no separate knower left standing apart to hold a prize. And each time you think you've finally got it, we know not arrives like a blade and cuts it down, and you are made a beginner again, fluid, open, on your knees in wonder rather than puffed up with certainty. The fool is sure. The sage stands in awe.
And here it folds into summa iru — be still. The mind that strains and reaches and calculates can never arrive; it only stirs the water. So stop. Set down the unbearable burden of having to figure existence out, to master it, to be the one with the answer. "We know not" unclenches the fist of the mind, and what's left is not defeat but rest — a holy not-knowing in which life can at last be lived in trust and surrender to Śiva, the way a child lives, who does not know how the world works and is therefore free. He must have said it not with a sigh but with a twinkle: the laugh of one who has seen through the whole game of knowing, and found, on the far side of it, only stillness, and only Śiva.